N-(4 substituted phenyl)-anthranilic acid hydroxamate esters

ABSTRACT

The present invention relates to oxygenated esters of 4-substituted-phenylamino benzhydroxamic acid derivatives, pharmaceutical compositions and methods of use thereof.

This application is a continuation of application Ser. No. 10/349,801,filed Jan. 23, 2003 now U.S. Pat. No. 6,891,066, which claims thebenefit of U.S. Provisional Application No. 60/351,201 filed Jan. 23,2002, the contents of which are hereby incorporated by reference intheir entireties.

FIELD OF THE INVENTION

The present invention relates to oxygenated esters of4-substituted-phenylamino benzhydroxamic acid derivatives,pharmaceutical compositions and methods of use thereof.

BACKGROUND OF THE INVENTION

MAPK/ERK Kinase (“MEK”) enzymes are dual specificity kinases involvedin, for example, immunomodulation, inflammation, and proliferativediseases such as cancer and restenosis.

Proliferative diseases are caused by a defect in the intracellularsignaling system, or the signal transduction mechanism of certainproteins. Defects include a change either in the intrinsic activity orin the cellular concentration of one or more signaling proteins in thesignaling cascade. The cell may produce a growth factor that binds toits own receptors, resulting in an autocrine loop, which continuallystimulates proliferation. Mutations or overexpression of intracellularsignaling proteins can lead to spurious mitogenic signals within thecell. Some of the most common mutations occur in genes encoding theprotein known as Ras, a G-protein that is activated when bound to GTP,and inactivated when bound to GDP. The above-mentioned growth factorreceptors, and many other mitogenic receptors, when activated, lead toRas being converted from the GDP-bound state to the GTP-bound state.This signal is an absolute prerequisite for proliferation in most celltypes. Defects in this signaling system, especially in the deactivationof the Ras-GTP complex, are common in cancers, and lead to the signalingcascade below Ras being chronically activated.

Activated Ras leads in turn to the activation of a cascade ofserine/threonine kinases. One of the groups of kinases known to requirean active Ras-GTP for its own activation is the Raf family. These inturn activate MEK (e.g., MEK₁ and MEK₂) which then activates the MAPkinase, ERK (ERK₁ and ERK₂). Activation of MAP kinase by mitogensappears to be essential for proliferation; constitutive activation ofthis kinase is sufficient to induce cellular transformation. Blockade ofdownstream Ras signaling, for example by use of a dominant negativeRaf-1 protein, can completely inhibit mitogenesis, whether induced fromcell surface receptors or from oncogenic Ras mutants. Although Ras isnot itself a protein kinase, it participates in the activation of Rafand other kinases, most likely through a phosphorylation mechanism. Onceactivated, Raf and other kinases phosphorylate MEK on two closelyadjacent serine residues, S²¹⁸ and S²²² in the case of MEK-1, which arethe prerequisite for activation of MEK as a kinase. MEK in turnphosphorylates MAP kinase on both a tyrosine, Y¹⁸⁵, and a threonineresidue, T¹⁸³, separated by a single amino acid. This doublephosphorylation activates MAP kinase at least 100-fold. Activated MAPkinase can then catalyze the phosphorylation of a large number ofproteins, including several transcription factors and other kinaes. Manyof these MAP kinase phosphorylations are mitogenically activating forthe target protein, such as a kinase, a transcription factor, or anothercellular protein. In addition to Raf-1 and MEKK, other kinases activateMEK, and MEK itself appears to be a signal integrating kinase. Currentunderstanding is that MEK is highly specific for the phosphorylation ofMAP kinase. In fact, no substrate for MEK other than the MAP kinase,ERK, has been demonstrated to date and MEK does not phosphorylatepeptides based on the MAP kinase phosphorylation sequence, or evenphosphorylate denatured MAP kinase. MEK also appears to associatestrongly with MAP kinase prior to phosphorylating it, suggesting thatphosphorylation of MAP kinase by MEK may require a prior stronginteraction between the two proteins. Both this requirement and theunusual specificity of MEK are suggestive that it may have enoughdifference in its mechanism of action to other protein kinases thatselective inhibitors of MEK, possibly operating through allostericmechanisms rather than through the usual blockade of the ATP bindingsite, may be found.

It has been found that the compounds of the present invention areinhibitors of MEK and are useful in the treatment of a variety ofproliferative disease states, such as conditions related to thehyperactivity of MEK, as well as diseases modulated by the MEK cascade.

SUMMARY OF THE INVENTION

The compounds of Formula I are a sub-genus of the genus disclosed in WO00/41505, which is PCT Application No. PCT/US99/30491. Surprisingly, thecompounds of the present invention have unexpectedly superior propertiesas MEK inhibitors.

The present invention provides a compound of formula

wherein

-   W is

-   R₂ is hydrogen, methyl, fluorine, or chlorine;-   R₃ is hydrogen or fluorine;-   R₄ is C₁₋₆ alkyl, C₂₋₄ alkenyl, C₂₋₆ alkynyl, C₃₋₆ cycloalkyl,    —(CH₂)—C₃₋₆ cycloalkyl, —O—(C₁₋₄ alkyl), —S—(C₁₋₂ alkyl), —SO₂CH₃,    —SO₂NR₆R₇, —C≡C—(CH₂)_(n)NH₂, —C═C(CH₂)_(n)OH, —C═C—(CH₂)_(n)NH₂,    —(CH₂)_(m)NH₂, —(CH₂)_(m)NHCH₃, —(CH₂)_(m)N(CH₃)₂, —(CH₂)_(m)OR₈,    —(CH₂)_(q)CF₃, —C≡CCF₃, —CH═CHCF₃, —CH₂CHCF₂, or —CH═CF₂, wherein    the C₁₋₆ alkyl and C₂₋₆ alkynyl are optionally substituted with    between 1 and 3 substituents selected from hydroxy and alkyl;-   m is 1 to 4;-   n is 1 to 2;-   q is 0 to 2;-   R₅ is hydrogen or chlorine;-   R₆ and R₇ are each independently hydrogen, methyl, or ethyl;    and pharmaceutically acceptable salts, (C₁₋₆) amides and (C₁₋₆)    esters thereof.

Also provided by the present invention are compounds of Formula I,wherein

-   W is

The present invention also provides compounds of Formula I, wherein R₂is hydrogen, fluorine, or chlorine.

Additionally, the present invention provides compounds of Formula I,wherein R₄ is C₁₋₆ alkyl, C₂₋₄ alkenyl, C₂₋₃ alkynyl, —(CH₂)_(m)OR₆,—S—(C₁₋₂ alkyl) or —SO₂CH₃; R₄ is C₁₋₆ alkyl; R₄ is ethyl; R₄ is C₂₋₄alkenyl or C₂₋₃ alkynyl; R₄ is vinyl; R₄ is —(CH₂)_(m)OR₆; or R₄ is—(CH₂)_(q)CF₃, —CH₂CHCF₂, or —CH═CF₂.

Also provided by the present invention are compounds of Formula I,wherein R₅ is hydrogen.

The invention also provides a pharmaceutical composition comprising acompound of Formula I and a pharmaceutically acceptable carrier.

Additionally, the invention provides a method of treating aproliferative disease in a patient in need thereof comprisingadministering a therapeutically effective amount of a compound ofFormula I.

The invention also provides the use of a compound of Formula I for themanufacture of a medicament for the treatment of a proliferativedisease.

Furthermore, the invention provides methods of treating cancer,restenosis, psoriasis, autoimmune disease, atherosclerosis,osteoarthritis, rheumatoid arthritis, heart failure, chronic pain, andneuropathic pain in a patient in need thereof comprising administering atherapeutically effective amount of a compound of Formula I.

The invention also provides the use of a compound of Formula I for themanufacture of a medicament for the treatment of cancer, restenosis,psoriasis, autoimmune disease, atherosclerosis, osteoarthritis,rheumatoid arthritis, heart failure, chronic pain, and neuropathic pain.

In addition, the invention provides a method for treating cancer in apatient in need thereof comprising administering a therapeuticallyeffective amount of a compound of Formula I in combination withradiation therapy or at least one chemotherapeutic agent.

DETAILED DESCRIPTION OF THE INVENTION

Certain terms are defined below and by their usage throughout thisdisclosure.

The terms “halogen” or “halo” in the present invention refer to afluorine, bromine, chlorine, and iodine atom or fluoro, bromo, chloro,and iodo. The terms fluorine and fluoro, for example, are understood tobe equivalent herein.

Alkyl groups, such as “C₁₋₆ alkyl”, include aliphatic chains (i.e.,hydrocarbyl or hydrocarbon radical structures containing hydrogen andcarbon atoms) with a free valence. Alkyl groups are understood toinclude straight chain and branched structures. Examples include methyl,ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, t-butyl, pentyl,2-pentyl, 3-pentyl, isopentyl, neopentyl, (R)-2-methylbutyl,(S)-2-methylbutyl, 3-methylbutyl, 2,3-dimethylpropyl, hexyl, and thelike. The term “C₁₋₆ alkyl” includes within its definition the terms“C₁₋₄ alkyl” and “C₁₋₂ alkyl”.

Alkenyl groups are analogous to alkyl groups, but have at least onedouble bond (two adjacent sp² carbon atoms). Depending on the placementof a double bond and substituents, if any, the geometry of the doublebond may be entgegen (E), or zusammen (Z), cis, or trans. Similarly,alkynyl groups have at least one triple bond (two adjacent sp carbonatoms). Unsaturated alkenyl or alkynyl groups may have one or moredouble or triple bonds, respectively, or a mixture thereof. Like alkylgroups, unsaturated groups may be straight chain or branched. Examplesof alkenyls and alkynyls include vinyl, allyl, 2-methyl-2-propenyl,cis-2-butenyl, trans-2-butenyl, and acetyl.

Cycloalkyl groups, such as C₃₋₆ cycloalkyl, refer to a saturatedhydrocarbon ring structure containing from 3 to 6 atoms. Typical C₃₋₆cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl,cyclohexyl, and the like.

The present invention includes the hydrates and the pharmaceuticallyacceptable salts and solvates of the compounds defined by Formula I. Thecompounds of this invention can possess a sufficiently basic functionalgroup, and accordingly react with any of a number of inorganic andorganic acids, to form a pharmaceutically acceptable salt.

The term “pharmaceutically acceptable salt” as used herein, refers tosalts of the compounds of Formula I which are substantially non-toxic toliving organisms. Typical pharmaceutically acceptable salts includethose salts prepared by reaction of the compounds of the presentinvention with a pharmaceutically acceptable mineral or organic acid.Such salts are also known as acid addition salts. Such salts include thepharmaceutically acceptable salts listed in Journal of PharmaceuticalScience, 1977; 66:2–19, which are known to the skilled artisan.

Acids commonly employed to form acid addition salts are inorganic acidssuch as hydrochloric acid, hydrobromic acid, hydroiodic acid, sulfuricacid, phosphoric acid, and the like, and organic acids such asp-toluenesulfonic, methanesulfonic acid, benzenesulfonic acid, oxalicacid, p-bromophenylsulfonic acid, carbonic acid, succinic acid, citricacid, benzoic acid, acetic acid, and the like. Example of suchpharmaceutically acceptable salts are the sulfate, pyrosulfate,bisulfate, sulfite, bisulfite, phosphate, monohydrogenphosphate,dihydrogenphosphate, metaphosphate, pyrophosphate, bromide,hydrobromide, iodide, acetate, propionate, decanoate, caprate,caprylate, acrylate, ascorbate, formate, hydrochloride, dihydrochloride,isobutyrate, caproate, heptanoate, propiolate, glucuronate, glutamate,propionate, phenylpropionate, salicylate, oxalate, malonate, succinate,suberate, sebacate, fumarate, malate, maleate, hydroxymateate,mandelate, mesylate, nicotinate, isonicotinate, cinnamate, hippurate,nitrate, stearate, phthalate, teraphthalate, butyne-1,4-dioate,butyne-1,4-dicarboxylate, hexyne-1,4-dicarboxylate, hexyne-1,6-dioate,benzoate, chlorobenzoate, methylbenzoate, hydrozybenzoate,methoxybenzoate, dinitrobenzoate, o-acetoxybenzoate,naphthalene-2-benzoate, phthalate, p-toluenesulfonate,p-bromobenzenesulfonate, p-chlorobenzenesulfonate, xylenesulfonate,phenylacetate, trifluoroacetate, phenylpropionate, phenylbutyrate,citrate, lactate, α-hydroxybutyrate, glycolate, tartrate, hemi-tartrate,benzenesulfonate, methanesulfonate, ethanesulfonate, propanesulfonate,hydroxyethanesulfonate, 1-naphthalenesulfonate, 2-naphthalenesulfonate,1,5-naphthalenedisulfonate, mandelate, tartarate, and the like. Apreferred pharmaceutically acceptable salt is hydrochloride.

It should be recognized that the particular counterion forming a part ofany salt of this inventions is usually not of a critical nature, so longas the salt as a whole is pharmacologically acceptable and as long asthe counterion does not contribute undesired qualities to the salt as awhole. It is further understood that such salts may exist as a hydrate.

As used herein, the term “stereoisomer” refers to a compound made up ofthe same atoms bonded by the same bonds but having differentthree-dimensional structures which are not interchangeable. Thethree-dimensional structures are called configurations. As used herein,the term “enantiomer” refers to each of two stereoisomers whosemolecules are nonsuperimposable mirror images of one another. The term“chiral center” refers to a carbon atom to which four different groupsare attached. As used herein, the term “diastereomers” refers tostereoisomers which are not enantiomers. The terms “racemate” or“racemic mixture” refer to a mixture of enantiomers.

The enantiomers of compounds of the present invention can be resolved byone of ordinary skill in the art using standard techniques well-known inthe art, such as those described by J. Jacques, et al., “Enantiomers,Racemates, and Resolutions”, John Wiley and Sons, Inc 1981. Examples ofresolutions include recrystallization techniques or chiralchromatography.

Some of the compounds of the present invention have one or more chiralcenters and may exist in a variety of stereoisomeric configurations. Asa consequence of these chiral centers, the compounds of the presentinvention occur as racemates, mixtures of enantiomers and as individualenantiomers, as well as diastereomers and mixtures of diastereomers. Allsuch racemates, enantiomers, and diastereomers are within the scope ofthe present invention.

The compounds of Formula I can be prepared by techniques and proceduresreadily available to one of ordinary skill in the art, for example byfollowing the procedures as set forth in the following Schemes, oranalogous variants thereof. These synthetic strategies are furtherexemplified in examples below. These schemes are not intended to limitthe scope of the invention in any way.

As used herein, the following terms have the meanings indicated: “BOC”refers to tert-butoxycarbonyl; Celite® refers to a filter agent which isacid washed and approximately 95% SiO₂; “DMA” refers toN,N-dimethylacetamide; “DMT-MM” refers to4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride;“EtOAc” refers to ethyl acetate; “Et₂O” refers to diethyl ether; “EtOH”refers to ethanol; “h” refers to hours; “LiHMDS” refers to lithium1,1,1,3,3,3-hexamethyldisilazane or lithium bis(trimethylsilylamide);“Lindlar catalyst” refers to a Pd/CaCO₃ catalyst washed with Pb(OAc)₂;“Me” refers to methyl; “MeOH” refers to methanol; “MsCl” refers tomethane sulfonyl chloride; “Pd/C” refers to palladium on carbon; “PE”refers to petroleum ether which can be substituted with “hexanes”;“(Ph₃P)₂PdCl₂” refers to dichlorobis(triphenylphosphine)palladium(II);“(Ph₃P)₄Pd” refers to tetrakis(triphenylphosphine)palladium(0); “PyBop”refers to benzotriazole-1-yl-oxy-tris-pyrrolidino-phosphoniumhexafluorophosphate; “RT” refers to room temperature; “TEA” refers totriethylamine; “TFA” refers to trifluoroacetic acid; “THF” refers to“tetrahydrofuran; “TLC” refers to thin layer chromatography; and “TMS”refers to trimethylsilyl. All other terms and substituents, unlessotherwise indicated, are previously defined. The reagents and startingmaterials are readily available to one of ordinary skill in the art.Schemes 1 and 2 provide syntheses of the compounds of Formula I.

In Scheme 1, Step A, a 2-(arylamino)-benzoic acid or diphenylamine (3)is prepared from the coupling of a suitable benzoic acid (1) and asuitable aniline (2) in the presence of a strong base, for example,lithium 1,1,1,3,3,3-hexamethyldisilazane (LiHMDS) or lithiumdiisopropylamide, in a polar aprotic solvent such as tetrahydrofuran,acetonitrile or dimethylformamide. For example, the aniline (2) and thebenzoic acid (1) are dissolved in a suitable organic solvent and cooledto about −78° C. under nitrogen. The suspension is treated with anexcess of a suitable base, such as LiHMDS, and allowed to warm to roomtemperature. The reaction is typically complete within about 2 hours toabout 5 days. The resulting benzoic acid (3) can be isolated by removingthe solvent, for example by evaporation under reduced pressure or byfiltering the precipitated solid through Celite® and washing with asuitable solvent. The benzoic acid (3) can be further purified, ifdesired, by standard methods such as chromatography, crystallization, ordistillation.

In Scheme 1, Step B, the compounds of Formula I are generally obtainedby the union of 2-(arylamino)-benzoic acid (3) with an alkoxylamine (4)by the action of a peptide coupling agent in the presence of a base, ifnecessary. It is understood that the alkoxylamine (4) may be suitablyprotected. In such instances, Scheme 1 may be modified to include aremoval of the protecting group by a procedure known in the art.Preferred coupling agents include 1,1′-carbonyldiimidazole (CDI),lithium bis (trimethylsilylamide) (LiHMDS), diphenylphosphinic chloride(DPP-Cl), benzotriazol-yl-oxy-tripyrolidinophosphoniumhexafluorophosphate (PyBOP),benzotriazol-1-yloxy-tris(dimethylamino)phosphonium hexafluorophosphate(BOP), N,N′-dicyclohexylcarbodiimide (DCC), or1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDCI).Preferred bases include diisopropylethylamine, triethylamine,4-methylmorpholine, or pyridine or a substituted pyridine, for example,4-dimethyaminopyridine or 2,6-dimethylpyridine. Preferred solvents arepolar aprotic solvents such as dichloromethane, tetrahydrofuran, ordimethylformamide. The reactions are generally carried out at atemperature between about −78° C. to about 25° C., and are normallycomplete within about 1 hour to about 5 days. The product amide can beisolated by removing the solvent, for example by evaporation underreduced pressure, and further purified, if desired, by standard methodssuch as chromatography, crystallization, or distillation.

It would be understood by one of skill in the art that the substituentat R₄ on the diphenylamine (3) can be reduced before the couplingreaction. The reduction is performed on alkene or alkyne derivativesunder conditions known in the art, such as through hydrogenation, forexample with Pd/C under an atmosphere of hydrogen.

Alternately, the compounds of formula I are generally prepared as shownin Scheme 1, steps C and D by the contact of alkoxyamine (4) with“activated” benzoic acid derivatives (3a), wherein the activating group“X” completes an acid halide, anhydride, mixed anhydride, or anactivated ester, such as a pentafluorophenyl ester, nitrophenyl ester orthioester. Preferred bases include diisopropylethylamine, triethylamine,4-methylmorpholine, imidazole, pyridine or a substituted pyridine, forexample, 4-dimethyaminopyridine or 2,6-dimethylpyridine. Preferredsolvents are polar aprotic solvents such as dichloromethane,tetrahydrofuran, dimethylformamide, or N,N-dimethylacetamide.

In Scheme 2, Step A, a 4-iodo phenylamino benzoic acid (3′) is preparedfrom the union of a suitable benzoic acid (1) and a suitable4-iodoaniline (2′), in the presence of a strong base, for example,lithium bis(trimethylsilylamide) or lithiumdiisopropylamide, in a polaraprotic solvent such as tetrahydrofuran or acetonitrile. For example,lithum bis(trimethylsilylamide) is added to a solution of the benzoicacid (1) in tetrahydrofuran and added to a separate solution of the4-iodoaniline (2′). Each reaction is carried out at about −78° undernitrogen. The benzoic acid (1) solution is transferred to the4-iodoaniline (2′) solution using positive nitrogen pressure and stirredfor 6–12 hours at ambient. The resulting 4-iodophenylamino benzoic acid(3′) is isolated by removing the solvent, for example by filtering theprecipitated solid through Celite® and washing with a suitable solvent,and further purified, if desired, by standard methods such aschromatography, crystallization, or distillation.

In Scheme 2, Step B, the 4-iodo phenylamino benzoic acid (3′) isprotected as the methyl 4-iodo-phenylamino benzoate (5) using a suitablereagent, such as TMS-diazomethane. For example, a suitable reagent, suchas TMS-diazomethane is added dropwise to a solution of the benzoic acid(3′) in a suitable solvent, such as a mixture of diethyl ether and andmethanol. This mixture is stirred at room temperature for about 6 hoursto 2 days, followed by quenching of the excess reagent with a suitableweak acid, such as acetic acid, to provide the methyl ester (5).

In Scheme 2, Step C, the 4-iodo phenylamino benzoic acid (3′) is coupledwith an alkoxylamine (4) according to the general procedure of Scheme 1,Step B or Scheme 1, Steps C and D to provide the 4-iodo-phenylaminobenzamide (6).

In Scheme 2, Step D, the methyl 4-substituted-phenylamino benzoate (5a)are prepared from the methyl 4-iodo-phenylamino benzoate (5), bytransition metal-promoted coupling with reagent M-R₄ (7) in a suitablesolvent such as triethylamine, tetrahydrofuran or dimethylformamide. Theentire mixture is stirred from about 2 to 24 hours at room temperature.The transition metal-promoted coupling may be carried out with apalladium(0) or palladium (II) coupling agent, such as (Ph₃P)₄Pd or(Ph₃P)₂PdCl₂. M is defined as a functional group known to transfer acarbon radical fragment in transition metal-promoted coupling processes.Examples of a suitable M group include trialkylstannyl, trialkylsilyl,trimethylsilyl, zinc, copper, boron, magnesium and lithium. It would beunderstood by one of skill in the art that the substituent R₄ may befurther transformed, such as by oxidation, reduction, deprotection, orhydrogenation. The substituent R₄ may also be transformed into adifferent R₄ through standard synthetic procedures known to one of skillin the art. The resulting compound of formula I, as well as theprotected Formula I compound, can be isolated by removing the solvent,for example by evaporation under reduced pressure, and further purified,if desired, by standard methods such as chromatography, crystallization,or distillation.

In Scheme 2, Step E, the compounds of Formula I are prepared from the4-iodo-phenylamino benzamide (6), by transition metal-promoted couplingwith reagent M-R₄ (7) according to the general procedure of Scheme 2,Step D.

In Scheme 2, Step F, the methyl 4-substituted-phenylamino benzoate (5a)is deprotected in a manner known to one of skill in the art, forexample, aqueous NaOH in EtOH, then coupled with an alkoxylamine (4)according to the general procedure of Scheme 1, Step B.

In Scheme 2, Step G, R₄, if saturated, can be converted to a fullysaturated substituent through hydrogenation, for example with Pd/C underan atmosphere of hydrogen.

In Scheme 3, Step A, the methyl 4-iodo-phenylamino benzoate (5) isprepared according to the procedure of Scheme 2, Step B.

In Scheme 3, Step B. the methyl 4-alkene substituted benzoate (5b) isprepared according to the procedure of Scheme 2, steps D and E, wherethe transition metal-promoted coupling of the methyl 4-iodo-phenylaminobenzoate (5) is carried out using a suitable reagent such asallyltributyltin or tetravinyltin.

In Scheme 3, Step C the methyl 4-alkene substituted benzoate (5b) isdeprotected according to the procedure of Scheme 2, Step F. then coupledwith an alkoxylamine (4) according to the general procedure of Scheme 1,Step B to provide a compound of formula I wherein R₄ is C₂₋₃ alkene(formula Ia).

In Scheme 3, Step D, compounds of formula (5c) were prepared from themethyl 4-alkene substituted benzoate (5b) by reaction of the double bondat the 4′ position of the phenylamine with ozone and NaBH₄, to give thealcohol (5c).

In Scheme 3, step E, the double bond at the 4′ position of thephenylamine of formula Ia may be treated with OsO₄ for example, in orderto give the corresponding diol, which is a compound of formula I whereinR₄ is alkyl substituted with 2 hydroxy substituents (formula Ib).

In Scheme 3, Step F, the methyl ester group of the alcohol compound (5c)is deprotected according to the procedure of Scheme 2, Step F, thencoupled with an alkoxylamine (4) according to the general procedure ofScheme 1, Step B to provide a compound of formula I wherein R₄ is alkylsubstituted with a hydroxy substituent (formula Ic).

In Scheme 4, Step A, the methyl 4-iodo-phenylamino benzoate (5) isprepared from the 4-iodo phenylamino benzoic acid (3′) according to thegeneral procedure of Scheme 2, Step B.

In Scheme 4, Step B, the compounds (5d) are prepared according to theprocedure of Scheme 2, Steps D and E, where the transitionmetal-promoting coupling of the methyl 4-iodo-phenylamino benzoate (5)is carried out using a suitable reagent, such as propargyl alcohol.

In Scheme 4, Step C, the compound (5d) is converted to the fullysaturated carboxylic acid through hydrogenation, for example with Pd/Cunder an atmosphere of hydrogen. The methyl ester of the compound (5d)is then deprotected according to the procedure of Scheme 2, Step F.

In Scheme 4, step D, the alcohol (5e) is coupled with an alkoxylamine(4) according to the general procedure of Scheme 1, Step B.

In Scheme 4, step E, the compound (5f) is dissolved in a suitablesolvent such as tetrahydrofuran and reacted with methanesulfonylchloride to give the intermediate mesylate, then NaI in EtOAc to givethe iodide compound (5g).

In Scheme 4, steps F and G, the iodide compound (5g) is reacted withmethylamine and dimethylamine respectively to give compounds of formula1 wherein m is 3 and R₄ is —(CH₂)_(m)NHCH₃ (formula Id) and—(CH₂)_(m)N(CH₃)₂ (formula Ie).

In Scheme 4A, Step A, the iodide compound is reacted with a suitableamine to provide the amide substituted methyl ester compound.

In Scheme 4A, Step B, the methyl ester compound is deprotected accordingto the general procedure of Scheme 4, Step C.

In Scheme 4A, Step C, the alcohol (5e) is coupled with an alkoxylamine(4) according to the general procedure of Scheme 1, Step B to providethe compound of formula I where R₄ is —(CH₂)NR₆R₇.

In Scheme 5, Step A, the alcohol compound (5c) is reacted withmethanesulfonyl chloride to give the mesylate (5h) according to thegeneral procedure of Scheme 4, Step E.

In Scheme 5, Step B, the mesylate (5d) is reacted with NaI in ethylacetate to provide the iodide compound (5i).

In Scheme 5, Step C, the iodide compound (5i) is reacted with a suitablealkoxide to provide the compound (5j).

In Scheme 5, Step D, the methyl ester of the compound (5j) isdeprotected according to the procedure of Scheme 2, Step F to providethe carboxylic acid (5k).

In Scheme 5, Step E, the carboxylic acid (5k) is coupled with analkoxylamine (4) according to the general procedure of Scheme 1, Step Bto provide the compound of formula I wherein R₄ is —(CH₂)_(m)OR₆(formula If).

In Scheme 6, Step A, the benzoic acid (5k) is activated according to thegeneral procedure of Scheme 1, Step C to provide the pentafluorophenylcompound (5l).

In Scheme 6, Step B, sodium borohydride was added to a solution of thepentafluorophenyl compound (5l) in a suitable solvent, such astetrahydrofuran to provide the compound of formula I wherein R₄ ismethyl substituted with hydroxy (formula Ig).

The aniline (2) can be prepared by techniques and procedures readilyavailable to one of ordinary skill in the art and by following theprocedures as set forth in the following Schemes, or analogous variantsthereof. These Schemes are not intended to limit the scope of theinvention in any way.

In Scheme 7, Step A, the alkynylaniline (2a) is prepared via Sonogashiracoupling with a suitable 4-iodoaniline (5). For example, a 4-iodoaniline(5), such as 2-fluoro-4-iodoaniline, is combined with CuI and(Ph₃P)₂PdCl₂ under nitrogen. A suitable acetylene derivative (8) isadded in a suitable solvent, such as TEA, and the entire mixture isstirred from about 2 to 24 hours at room temperature. The resultingalkynylaniline (2a) can be isolated by removing the solvent, for exampleby evaporation under reduced pressure, and further purified, if desired,by standard methods such as chromatography, crystallization, ordistillation. It is understood that the alkynylaniline (2a) may besuitably protected. In such instances, Scheme 7 may be modified toinclude removal of a protecting group by a procedure known in the art.

In Scheme 7, Step B, alkynylaniline (2a) is reduced via hydrogenation toprovide the aniline (2b). The alkynylaniline (2a) is dissolved in asuitable solvent, such as absolute ethanol, in the presence of a metalcatalyst, such as palladium on carbon. This mixture is stirred under anatmosphere of hydrogen from about 1 to 24 hours at room temperature. Theresulting aniline (2b) can be isolated by removing the solvent, forexample by evaporation under reduced pressure, and further purified, ifdesired, by standard methods such as chromatography, crystallization, ordistillation.

In Scheme 7, Step C, alkynylaniline (2a) is partially reduced viahydrogenation to provide the alkenylaniline (2c). For example, thealkynylaniline (2a) is dissolved in a suitable solvent, such astetrahydrofuran, in the presence of a catalyst, such as Lindlar catalystor palladium on carbon and, if desired, a suitable compound whichdisrupts the actions of the catalyst, such as quinoline or pyridine.This mixture is stirred under an atmosphere of hydrogen from about 1 to24 hours at room temperature. The resulting alkenylaniline (2c) can beisolated by removing the solvent, for example by evaporation underreduced pressure, and further purified, if desired, by standard methodssuch as chromatography, crystallization, or distillation.

In Scheme 8, a suitably substituted para-nitrostyrene is reacted withdimethyloxosulfonium methylide to form the substitutedpara-nitrocyclopropylbenzene. Reduction of para-nitrocyclopropylbenzenewith iron in the presence of weak acid gives the desired aniline.

In Scheme 9, the suitable ortho-substituted acetamide is reacted withbromocyclobutane, bromocyclopropane, or bromocyclohexane under typicalFriedel-Craft conditions, as known to one of skill in the art, to givethe desired para-cycloalkylanilines.

In Scheme 10, a suitable ortho-substituted acetamide is reacted with asuitable bromomethylcycloalkane under typical Friedel-Craft conditions,as known to one of skill in the art, to givepara-cycloalkylmethylacetamides. The acetamide is deprotected underconditions known to one of skill in the art to provide the desiredpara-cycloalkylmethylanilines.

In Scheme 11, Step A, an alkoxide (10) is reacted with a4-tert-butoxycarbonylamino-3-substituted-benzyl bromide (9), such as4-tert-butoxycarbonylamino-3-fluorobenzyl bromide (J. Med. Chem., 2000;43:5017). In Step B, the BOC protecting group of compound of structure(11) is hydrolized with, for example, TFA, to provide the desiredaniline (2d).

In Scheme 11A, Step A, a suitable 3-substituted-4-nitrophenol (12), suchas 3-fluoro-4-nitrophenol, is alkylated with a compound of structure(13) in the presence of a suitable base to provide a compound ofstructure (14). In Step B, compound (14) is reduced via hydrogenation inthe presence of a metal catalyst, such as palladium on carbon, in anatmosphere of hydrogen to provide the desired aniline (2e).

In Scheme 12, a suitable 4-(aminophenyl)thiocyanate(15), is alkylatedwith a compound of structure (13′) in the presence of a suitablenucleophilic base to provide an alkylthio compound of structure (2f).After reaction under standard conditions to form the diphenylamine (3),wherein R₄ is —S—(alkyl), as in Scheme 1 above, this compound is thenoxidized to the corresponding sulfonyl compound, also generally, thediphenylamine (3), wherein R₄ is —SO₂—(alkyl).

In Scheme 12A, the proper ortho-substituted or unsubstituted aniline(5′) is acetylated with acetic anhydride in the presence oftrifluoromethanesulfonic acid indium salt to give the protected aniline(16). Chlorosulfonation in the typical manner, as known in the art,gives the sulfonyl chloride derivative (17) which is reacted with anexcess of a suitable amine (18) in a solvent such as dichloromethane ordichloroethane to give the protected para-aminobenzenesulfonamide (19).Acid-mediated deprotection in the appropriate solvent gives the desiredaniline (2g).

Alternatively, the desired aniline (2g) wherein R₂ is methyl, fluorineor chlorine, using compound (17) as the starting material can beprepared. Where R₂ is fluorine, the sulfonyl chloride derivative (17) isa compound known in the literature (German Patent DE 2630060, 1978).Similarly, where R₂ is methyl, the sulfonyl chloride derivative (17) isalso known in the literature (German Patent. DE 2750170, 1978). Finally,the sulfonyl chloride derivative (20) where R₂ is chlorine iscommercially available.

In addition to the procedure described in Scheme 12A, one of ordinaryskill in the art would appreciate that there are numerous ways ofacetylating anilines. For example, heating the aniline and aceticanhydride together in a suitable solvent, such as acetic acid, wouldachieve the same result.

As in Scheme 7, Step A above, the compounds of Formula I, wherein R₄ is—C≡C—(CH₂)_(n)OH are prepared via the Sonogashira coupling with asuitable 4-iodoaniline, such as 2-fluoro-4-iodoaniline, and anappropriately substituted acetylene, as shown in Scheme 13 above. Afterreaction with aniline (2h) under standard conditions to form thediphenylamine, as in Scheme 1 above, hydrolysis of thetetrahydropyranyl-protecting group under conditions known in the artprovides the desired compounds.

As in Scheme 7, Step A above, the compounds of Formula I, wherein R₄ is—(CH₂)_(m)OR₆, R₆═H or —C═C(CH₂)_(n)OH, are prepared via the Sonogashiracoupling with a suitable 4-iodoaniline, such as 2-fluoro-4-iodoaniline,and an appropriately substituted acetylene, as shown in Scheme 13 above.After reaction with aniline (2h) under standard conditions to form thediphenylamine, as in Scheme 1 above, and hydrolysis of thetetrahydropyranyl-protecting group under conditions known in the art,reduction via hydrogenation under the conditions as in Scheme 7, Steps Band C above, provides the desired compounds.

In Scheme 14, Step A, a suitable phenethyl alcohol (24) is prepared froma suitable 2-substituted-4-vinylaniline (23), such as2-fluoro-4-vinylaniline (Tetrahedron Letters, 1997; 38:7433), byhydroboration and oxidation. The alcohol (24) is protected as thephthalimide (25) in Step B followed by the Mitsunobu reaction in Step Cwith the compound of structure (26), which isN-BOC-2-nitrobenzenesulfonamide (Synlett, 1999:1301). The anilines (2i)and (2j) are provided by deprotection of the phthalimide, as shown inStep D or alternatively, alkylation (Tetrahedron Letters, 1997;38:5831), as shown in Step E and F, followed by deprotection of thephthalimide, as in Step G.

After reaction of the anilines (2i) and (2j) of Scheme 14, under theconditions as generally described in Scheme 1 above, a finaldeprotection (Synlett, 1999; 1301) provides the compounds of Formula 1wherein R₄ is —CH₂CH₂NH₂ or —CH₂CH₂NHCH₃.

In Scheme 15, Step A, a suitable amine (28) is reacted with a4-tert-butoxycarbonylamino-3-substituted-benzyl bromide (27), such as4-tert-butoxycarbonylamino-3-fluorobenzyl bromide (J. Med. Chem. 2000;43; 5017), followed by hydrolysis of the BOC protecting group of thecompound of structure (29) with, for example, TFA in Step B to providethe compound of structure (2k).

The compounds of Formula I, wherein R₄ is (CH₂)_(q)CF₃ and q is 0 areprepared according to the general procedure of Scheme 1 where thesuitable aniline (2) is the appropriate 4-trifluoromethylaniline (e.g.,2-fluoro; J. Org. Chem., 1985; 50:457).

In Scheme 16, Step A, the compounds of structure (32) are prepared by anUllmann condensation of a suitable 4-iodoaniline, such as2-fluoro-4-iodoaniline, with a perfluoroalkyl iodide (31) (e.g., N.Yoshino et. al., Bull. Chem. Soc. Jpn, 1992; 65:2141).

In Scheme 16, Step B, the desired anilines (21) are prepared fromcompound (32) by reductive removal of the benzylic fluorine atoms with asuitable reducting agent, such as LiAlH₄ (Tetrahedron Letters, 1996;37:4655).

In Scheme 17, the compounds of Formula I, R₄ is —C≡CCF₃ are prepared byNegishi coupling with 3,3,3-trifluoropropynyl zinc chloride (e.g. J.Fluorine Chem., 1987; 36:313 and 1992; 56:175).

In Scheme 17, the compounds of Formula I, wherein R₄ is —(CH₂)_(q)CF₃ or—CH═CHCF₃ and q is 2 are prepared by reduction of the analogous alkynes(33). Selective reduction of the alkynes (33) according to the generalprocedure of Scheme 7, Step C, provides the analogous alkenes.

In Scheme 18, the compounds of Formula I where R₄ is —CH₂CHCF₂, or—CH═CF₂ are provided by a synthetic route based on the procedure of J.Org. Chem., 1997; 62:7758. Thus, reaction of a suitable aniline (34),such 2-fluoro-4-iodoaniline with a suitable ethylene (35), such as2,2-difluoroiodoethylene, and zinc provides4-(2,2-difluorovinyl)-2-substituted-aniline (2m), which is reduced viahydrogenation in the presence of a metal catalyst, such as palladium oncarbon, in an atmosphere of hydrogen to provide4-(2,2-difluoroethyl)-2-substituted-aniline (2n).

In Scheme 19, Step A, a suitable acetic acid (35), such as phenylaceticacid, 3-fluorophenylacetic acid, 3-chlorophenylacetic acid, and3-methylphenylacetic acid, which are commercially available, is reducedto the respective alcohol (36) with borane-tetrahydrofuran complex.Alkylation of the primary alcohol in Step B with a suitable alkyl iodide(37) forms an ether (38), which is followed by nitration and mild ironreduction of the nitro group to provide the desired aniline (2o).

In Scheme 20, a suitable phenylproprionic acid or phenylbutyric acid(39) is reduced with borane-tetrahydrofuran in Step A to give thecorresponding alcohol (40). Aromatic nitration in Step B, followed bytosylation of the primary alcohol in Step C, displacement with theBOC-protected monomethylamine in Step D, and reduction of the nitrogroup with iron under mildly acidic conditions in Step E provides thedesired aniline. The Boc-protecting group is removed after formation ofthe Boc-protected desired diphenylamine product.

In Scheme 21, Step A, the proper acid starting material (41) is reducedwith borane-tetrahydrofuran to the primary alcohol (42). Aromaticnitration in Step B is followed by tosylation of the alcohol in Step C,displacement of tosylate with dimethylamine in Step D, and ironreduction of the nitro group in Step E provides the desired aniline(2p).

Scheme 22 demonstrates the Negishi coupling procedure, which is known toone of ordinary skill in the art.

The present invention also provides compounds of Formula I, wherein:

-   -   R₂ is hydrogen, fluorine, or chlorine; or R₂ is fluorine or        chlorine; or R₂ is fluorine;    -   R₄ is C₁₋₆ alkyl, C₂₋₃ alkenyl, C₂₋₃ alkynyl, —(CH₂)_(m)OR₆,        —S—(C₁₋₂ alkyl) or —SO₂CH₃; or R₄ is C₁₋₃ alkyl; or R₄ is ethyl;        or R₄ is C₂₋₄ alkenyl or C₂₋₃ alkynyl; or R₄ is vinyl; or R₄ is        —(CH₂)_(m)OR₆; or R₄ is —(CH₂)_(q)CF₃, —CH₂CHCF₂, or —CH═CF₂; or    -   R₅ is hydrogen.

Also provided by the present invention are compounds of the formula

wherein

-   -   W is

-   -   R₂ is hydrogen, fluorine, or chlorine;    -   R₃ is hydrogen or fluorine;    -   R₄ is C₁₋₆ alkyl, C₂₋₄ alkenyl, C₂₋₆ alkynyl, —S—(C₁₋₂ alkyl),        —SO₂CH₃, —C≡C—(CH₂)_(n)NH₂, —(CH₂)_(m)NH₂, —(CH₂)_(m)NHCH₃,        —(CH₂)_(m)N(CH₃)₂, or —(CH₂)_(m)OR₈, wherein the C₁₋₆ alkyl and        C₂₋₆ alkynyl are optionally substituted with between 1 and 3        substituents selected from hydroxy and alkyl;    -   m is 1 to 4;    -   n is 1 to 2;    -   q is 0 to 2;    -   R₅ is hydrogen or chlorine;    -   R₆ and R₇ are each independently hydrogen, methyl, or ethyl;    -   R₈ is independently methyl or ethyl;        and pharmaceutically acceptable salts thereof.

Additionally provided by the present invention are compounds of theformula

wherein

-   -   W is

-   -   R₂ is fluorine, or chlorine;    -   R₃ is hydrogen or fluorine;    -   R₄ is C₁₋₄ alkyl, C₂₋₃ alkenyl, C₂₋₄ alkynyl, —S—(C₁₋₂ alkyl),        —SO₂CH₃, —C≡C—(CH₂)_(n)NH₂, or —(CH₂)_(m)OR₈, wherein the C₁₋₄        alkyl and C₂₋₄ alkynyl are optionally substituted with between 1        and 3 substituents selected from hydroxy and alkyl;    -   m is 1 to 4;    -   n is 1 to 2;    -   q is 0 to 2;    -   R₅ is hydrogen or chlorine;    -   R₆ and R₇ are each independently hydrogen, methyl, or ethyl;    -   R₈ is independently methyl or ethyl;        and pharmaceutically acceptable salts thereof.

Compounds of the present invention include, but are not limited to thefollowing compounds:

-   2-[(4-Ethyl-2-fluorophenyl)amino]-3,4-difluoro-N-(2-hydroxyethoxy)benzamide;-   2-(2-Chloro-4-ethyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-[(2-fluoro-4-vinylphenyl)amino]-N-(2-hydroxyethoxy)benzamide;-   2-(2-Chloro-4-vinyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   2-[(4-Ethynyl-2-fluorophenyl)amino]-3,4-difluoro-N-(2-hydroxyethoxy)benzamide;-   3,4-Difluoro-N-(2-hydroxyethoxy)-2-[[4-(hydroxymethyl)phenyl]amino]benzamide;-   3,4-Difluoro-2-[[2-fluoro-4-(3-methoxypropyl)phenyl]amino]-N-(2-hydroxyethoxy)benzamide;-   3,4-Difluoro-2-[[2-fluoro-4-(methylthio)phenyl]amino]-N-(2-hydroxyethoxy)benzamide;-   3,4-Difluoro-2-[[2-fluoro-4-(ethylthio)phenyl]amino]-N-(2-hydroxyethoxy)benzamide;-   3,4-Difluoro-2-[[2-fluoro-4-(methylsulfonyl)phenyl]amino]-N-(2-hydroxyethoxy)benzamide;-   N-[(R−)2,3-Dihydroxy-propoxy]-2-(4-ethyl-2-fluoro-phenylamino)-3,4-difluoro-benzamide;-   2-(4-Ethyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-1-hydroxymethyl-ethoxy)-benzamide;-   3,4-Difluoro-2-(2-fluoro-4-methylanilino)-N-(2-hydroxyethoxy)benzamide;-   2-(4-Allyl-2-fluoroanilino)-3,4-difluoro-N-(2-hydroxyethoxy)benzamide;-   2-(2-Chloro-4-ethynyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   2-[4-(3-Amino-1-propynyl)-2-fluoroanilino]-3,4-difluoro-N-(2-hydroxyethoxy)benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(3-hydroxy-1-propynyl)anilino]-N-(2-hydroxyethoxy)benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(4-hydroxy-1-butynyl)anilino]-N-(2-hydroxyethoxy)benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(3-hydroxy-3-methyl-1-butynyl)anilino]-N-(2-hydroxyethoxy)benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(3-hydroxy-3-methyl-1-pentynyl)anilino]-N-(2-hydroxyethoxy)benzamide;-   2-[4-(3-Aminopropyl)-2-fluoroanilino]-3,4-difluoro-N-(2-hydroxyethoxy)benzamide;-   2-{4-[3-(Dimethylamino)propyl]-2-fluoroanilino}-3,4-difluoro-N-(2-hydroxyethoxy)benzamide;-   3,4-Difluoro-2-{2-fluoro-4-[3-(methylamino)propyl]anilino}-N-(2-hydroxyethoxy)benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(hydroxymethyl)anilino]-N-(2-hydroxyethoxy)benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(2-hydroxyethyl)anilino]-N-(2-hydroxyethoxy)benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(3-hydroxypropyl)anilino]-N-(2-hydroxyethoxy)benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(4-hydroxybutyl)anilino]-N-(2-hydroxyethoxy)benzamide;-   2-[4-(2,3-Dihydroxypropyl)-2-fluoroanilino]-3,4-difluoro-N-(2-hydroxyethoxy)benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(3-hydroxy-3-methylbutyl)anilino]-N-(2-hydroxyethoxy)benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(3-hydroxy-3-methylpentyl)anilino]-N-(2-hydroxyethoxy)benzamide;-   3,4-Difluoro-2-(2-fluoro-4-propylanilino)-N-(2-hydroxyethoxy)benzamide;    and-   2-(4-Butyl-2-fluoroanilino)-3,4-difluoro-N-(2-hydroxyethoxy)benzamide.

Also provided by the present invention are compounds which include, butare not limited to the following compounds:

-   2-(4-Ethyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   N-((R)-2,3-Dihydroxy-propoxy)-2-(4-ethyl-2-fluoro-phenylamino)-3,4-difluoro-benzamide;-   N-((S)-2,3-Dihydroxy-propoxy)-2-(4-ethyl-2-fluoro-phenylamino)-3,4-difluoro-benzamide;-   2-(4-Ethyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-1-hydroxymethyl-ethoxy)-benzamide;-   2-(4-Ethyl-2-methyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   2-(2-Chloro-4-ethyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   5-Chloro-2-(4-ethyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   5-Chloro-2-(4-ethyl-2-methyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   5-Chloro-2-(2-chloro-4-ethyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   2-(4-Ethynyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;    2-(4-Ethynyl-2-methyl-phenylamino)-4-fluoro-N-(2-hydroxy-ethoxy)-benzamide;-   N-((R)-2,3-Dihydroxy-propoxy)-2-(4-ethynyl-2-fluoro-phenylamino)-3,4-difluoro-benzamide;-   N-((S)-2,3-Dihydroxy-propoxy)-2-(4-ethynyl-2-fluoro-phenylamino)-3,4-difluoro-benzamide;-   2-(4-Ethynyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-1-hydroxymethyl-ethoxy)-benzamide;-   2-(4-Ethynyl-2-methyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   2-(2-Chloro-4-ethynyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   5-Chloro-2-(4-ethynyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   5-Chloro-2-(4-ethynyl-2-methyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   5-Chloro-2-(2-chloro-4-ethynyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-(2-fluoro-4-methyl-phenylamino)-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-(2-fluoro-4-propyl-phenylamino)-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-(2-fluoro-4-isopropyl-phenylamino)-N-(2-hydroxy-ethoxy)-benzamide;-   2-(4-Cyclopropyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   2-(4-Butyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-(2-fluoro-4-isobutyl-phenylamino)-N-(2-hydroxy-ethoxy)-benzamide;-   2-(4-sec-Butyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   2-(4-Cyclobutyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   2-(4-tert-Butyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-(2-fluoro-4-pentyl-phenylamino)-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(1-methyl-butyl)-phenylamino]-N-(2-hydroxy-ethoxy)-benzamide;-   2-[4-(1-Ethyl-propyl)-2-fluoro-phenylamino]-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   2-[4-(2,2-Dimethyl-propyl)-2-fluoro-phenylamino]-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-[2-fluoro-4-((R)-2-methyl-butyl)-phenylamino]-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-[2-fluoro-4-((S)-2-methyl-butyl)-phenylamino]-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(3-methyl-butyl)-phenylamino]-N-(2-hydroxy-ethoxy)-benzamide;-   2-(4-Cyclopentyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-(2-fluoro-4-hexyl-phenylamino)-N-(2-hydroxy-ethoxy)-benzamide;-   2-(4-Cyclohexyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   2-(4-Cyclopropylmethyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   2-(4-Allyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-(2-fluoro-4-vinyl-phenylamino)-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-(2-fluoro-4-hydroxymethyl-phenylamino)-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-N-(2-hydroxy-ethoxy)-2-(4-hydroxymethyl-phenylamino)-benzamide;-   3,4-Difluoro-2-(2-fluoro-4-methoxymethyl-phenylamino)-N-(2-hydroxy-ethoxy)-benzamide;-   2-(4-Ethoxymethyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(2-hydroxy-ethyl)-phenylamino]-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(3-hydroxy-propyl)-phenylamino]-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(3-methoxy-propyl)-phenylamino]-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-(2-fluoro-4-methoxy-phenylamino)-N-(2-hydroxy-ethoxy)-benzamide;-   2-(4-Ethoxy-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-(2-fluoro-4-propoxy-phenylamino)-N-(2-hydroxy-ethoxy)-benzamide;-   2-(4-Butoxy-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-(2-fluoro-4-methylsulfanyl-phenyl    amino)-N-(2-hydroxy-ethoxy)-benzamide;-   4-Fluoro-2-(2-fluoro-4-methylsulfanyl-phenylamino)-N-(2-hydroxy-ethoxy)-benzamide;-   2-(4-Ethylsulfanyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-(2-fluoro-4-methanesulfonyl-phenyl    amino)-N-(2-hydroxy-ethoxy)-benzamide;-   2-[4-(3-Amino-prop-1-ynyl)-2-fluoro-phenylamino]-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(3-hydroxy-prop-1-ynyl)-phenylamino]-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(4-hydroxy-but-1-ynyl)-phenylamino]-N-(2-hydroxy-ethoxy)-benzamide;-   2-[4-(2-Amino-ethyl)-2-fluoro-phenylamino]-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   2-[4-(3-Amino-propyl)-2-fluoro-phenylamino]-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   2-[4-(4-Amino-butyl)-2-fluoro-phenylamino]-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(2-methylamino-ethyl)-phenylamino]-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(3-methylamino-propyl)-phenylamino]-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(4-methylamino-butyl)-phenylamino]-N-(2-hydroxy-ethoxy)-benzamide;-   2-(4-Dimethylaminomethyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-(2-fluoro-4-sulfamoyl-phenylamino)-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-(2-fluoro-4-methylsulfamoyl-phenylamino)-N-(2-hydroxy-ethoxy)-benzamide;-   2-(4-Dimethylsulfamoyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-(2-fluoro-4-trifluoromethyl-phenylamino)-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(2,2,2-trifluoro-ethyl)-phenylamino]-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(3,3,3-trifluoro-propyl)-phenylamino]-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(4,4,4-trifluoro-butyl)-phenylamino]-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(5,5,5-trifluoro-pentyl)-phenylamino]-N-(2-hydroxy-ethoxy)-benzamide;-   3,4-Difluoro-2-[2-fluoro-4-(6,6,6-trifluoro-hexyl)-phenylamino]-N-(2-hydroxy-ethoxy)-benzamide;-   2-[4-(2,2-Difluoro-ethyl)-2-fluoro-phenyl    amino]-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide; and-   2-[4-(2,2-Difluoro-vinyl)-2-fluoro-phenyl    amino]-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide.

As used herein, the term “patient” refers to any warm-blooded animalsuch as, but not limited to, a human, horse, dog, guinea pig, or mouse.Preferably, the patient is human.

The term “treating” for purposes of the present invention refers totreatment, prophylaxis or prevention, amelioration or elimination of anamed condition once the condition has been established.

Selective MEK 1 or MEK 2 inhibitors are those compounds which inhibitthe MEK 1 or MEK 2 enzymes, respectively, without substantiallyinhibiting other enzymes such as MKK3, PKC, Cdk2A, phosphorylase kinase,EGF, and PDGF receptor kinases, and C-src. In general, a selective MEK 1or MEK 2 inhibitor has an IC₅₀ for MEK 1 or MEK 2 that is at leastone-fiftieth ( 1/50) that of its IC₅₀ for one of the above-named otherenzymes. Preferably, a selective inhibitor has an IC₅₀ that is at least1/100, more preferably 1/500, and even more preferably 1/1000, 1/5000,or less than that of its IC₅₀ or one or more of the above-named enzymes.

The disclosed compositions are useful as both prophylactic andtherapeutic treatments for diseases or conditions related to thehyperactivity of MEK, as well as diseases or conditions modulated by theMEK cascade. Examples include, but are not limited to, stroke, septicshock, heart failure, osteoarthritis, rheumatoid arthritis, organtransplant rejection, and a variety of tumors such as ovarian, lung,pancreatic, brain, prostatic, and colorectal.

The invention further relates to a method for treating proliferativediseases, such as cancer, restenosis, psoriasis, autoimmune disease, andatherosclerosis. Other aspects of the invention include methods fortreating MEK-related (including ras-related) cancers, whether solid orhematopoietic. Examples of cancers include brain, breast, lung, such asnon-small cell lung, ovarian, pancreatic, prostate, renal, colorectal,cervical, acute leukemia, and gastric cancer. Further aspects of theinvention include methods for treating or reducing the symptoms ofxenograft (cell(s), skin, limb, organ or bone marrow transplant)rejection, osteoarthritis, rheumatoid arthritis, cystic fibrosis,complications of diabetes (including diabetic retinopathy and diabeticnephropathy), hepatomegaly, cardiomegaly, stroke (such as acute focalischemic stroke and global cerebral ischemia), heart failure, septicshock, asthma, Alzheimer's disease, and chronic or neuropathic pain.Compounds of the invention are also useful as antiviral agents fortreating viral infections such as HIV, hepatitis (B) virus (HBV), humanpapilloma virus (HPV), cytomegalovirus (CMV), and Epstein-Barr virus(EBV). These methods include the step of administering to a patient inneed of such treatment, or suffering from such a disease or condition, atherapeutically effective amount of a disclosed compound of formula I orpharmaceutical composition thereof.

The term “chronic pain” for purposes of the present invention includes,but is not limited to, neuropathic pain, idiopathic pain, and painassociated with chronic alcoholism, vitamin deficiency, uremia, orhypothyroidism. Chronic pain is associated with numerous conditionsincluding, but not limited to, inflammation, arthritis, andpost-operative pain.

As used herein, the term “neuropathic pain” is associated with numerousconditions which include, but are not limited to, inflammation,postoperative pain, phantom limb pain, burn pain, gout, trigeminalneuralgia, acute herpetic and postherpetic pain, causalgia, diabeticneuropathy, plexus avulsion, neuroma, vasculitis, viral infection, crushinjury, constriction injury, tissue injury, limb amputation, arthritispain, and nerve injury between the peripheral nervous system and thecentral nervous system.

The invention also features methods of combination therapy, such as amethod for treating cancer, wherein the method further includesproviding radiation therapy or chemotherapy, for example, with mitoticinhibitors such as a taxane or a vinca alkaloid. Examples of mitoticinhibitors include paclitaxel, docetaxel, vincristine, vinblastine,vinorelbine, and vinflunine. Other therapeutic combinations include aMEK inhibitor of the invention and an anticancer agent such ascisplatin, 5-fluorouracil or 5-fluoro-2-4(1H,3H)-pyrimidinedione (5FU),flutamide, and gemcitabine.

The chemotherapy or radiation therapy may be administered before,concurrently, or after the administration of a disclosed compoundaccording to the needs of the patient.

Those skilled in the art will be able to determine, according to knownmethods, the appropriate therapeutically-effective amount or dosage of acompound of the present invention to administer to a patient, takinginto account factors such as age, weight, general health, the compoundadministered, the route of administration, the type of pain or conditionrequiring treatment, and the presence of other medications. In general,an effective amount or a therapeutically-effective amount will bebetween about 0.1 and about 1000 mg/kg per day, preferably between about1 and about 300 mg/kg body weight, and daily dosages will be betweenabout 10 and about 5000 mg for an adult subject of normal weight.Commercially available capsules or other formulations (such as liquidsand film-coated tablets) of 100, 200, 300, or 400 mg can be administeredaccording to the disclosed methods.

The compounds of the present invention are preferably formulated priorto administration. Therefore, another aspect of the present invention isa pharmaceutical composition comprising a compound of Formula I and apharmaceutically acceptable carrier. In making the compositions of thepresent invention, the active ingredient, such as a compound of FormulaI, will usually be mixed with a carrier, or diluted by a carrier orenclosed within a carrier. Dosage unit forms or pharmaceuticalcompositions include tablets, capsules, pills, powders, granules,aqueous and nonaqueous oral solutions and suspensions, and parenteralsolutions packaged in containers adapted for subdivision into individualdoses.

Dosage unit forms can be adapted for various methods of administration,including controlled release formulations, such as subcutaneousimplants. Administration methods include oral, rectal, parenteral(intravenous, intramuscular, subcutaneous), intracisternal,intravaginal, intraperitoneal, intravesical, local (drops, powders,ointments, gels, or cream), and by inhalation (a buccal or nasal spray).

Parenteral formulations include pharmaceutically acceptable aqueous ornonaqueous solutions, dispersion, suspensions, emulsions, and sterilepowders for the preparation thereof. Examples of carriers include water,ethanol, polyols (propylene glycol, polyethylene glycol), vegetableoils, and injectable organic esters such as ethyl oleate. Fluidity canbe maintained by the use of a coating such as lecithin, a surfactant, ormaintaining appropriate particle size. Carriers for solid dosage formsinclude (a) fillers or extenders, (b) binders, (c) humectants, (d)disintegrating agents, (e) solution retarders, (f) absorptionaccelerators, (g) adsorbants, (h) lubricants, (i) buffering agents, and(j) propellants.

Compositions may also contain adjuvants such as preserving, wetting,emulsifying, and dispensing agents; antimicrobial agents such asparabens, chlorobutanol, phenol, and sorbic acid; isotonic agents suchas a sugar or sodium chloride; absorption-prolonging agents such asaluminum monostearate and gelatin; and absorption-enhancing agents.

The following examples represent typical syntheses of the compounds ofthe present invention as described generally above. These examples areillustrative only and are not intended to limit the invention in anyway. The reagents and starting materials are readily available to one ofordinary skill in the art.

EXAMPLE 1

2-[(4-Ethyl-2-fluorophenyl)amino]-3,4-difluoro-N-(2-hydroxyethoxy)benzamide

Step A: Preparation of 2-fluoro-4-[(trimethylsilyl)ethynyl]aniline

2-Fluoro-4-iodoaniline (5.00 g, 21.1 mmol), CuI (90 mg, 0.42 mmol), and(Ph₃P)₂PdCl₂ (300 mg, 0.42 mmol) were weighed into a flask which wassealed and flushed with N₂. A solution of TMS-acetylene (2.28 g, 23.2mmol) in TEA (20 mL) was added, then the entire mixture stirred 15 hoursat room temperature. The reaction mixture was diluted with diethyl ether(200 mL), filtered through Celite®, then all solvents removed underreduced pressure. The resulting dark brown oil was purified byfiltration through a plug of flash silica (5% EtOAc/hexanes as eluant)to afford the desired product as a pale brown oil which rapidlysolidified to give a crystalline solid (3.85 g, 88%); m.p.(EtOAc/hexanes) 45–47° C. ¹H NMR (400 MHz, CDCl₃) δ 7.10 (dd, J=11.7,1.8 Hz, 1 H), 7.06 (ddd, J=8.3, 1.8, 1.0 Hz, 1 H), 6.66 (dd, J=9.4, 8.3Hz, 1 H), 3.86 (br s, 2 H), 0.22 (s, 9 H). Anal. Calcd for C₁₁H₁₄FNSi:C, 63.7; H, 6.8; N, 6.8. Found: C, 63.7; H, 6.9; N, 6.7.

Step B: Preparation of3,4-difluoro-2-[[2-fluoro-4(trimethylsilylethynyl)phenyl]amino]benzoicacid

A mixture of the product of Step A,2-fluoro-4-[(trimethylsilyl)ethynyl]aniline (3.85 g, 18.6 mmol) and2,3,4-trifluorobenzoic acid (3.27 g, 18.6 mmol) was dissolved in dry THF(25 mL). The flask was fitted with a pressure-equalising dropping funneland the entire apparatus evacuated and flushed with N₂. The solution wasthen cooled to −78° C. (acetone/dry ice) and a solution of 1.06 M LiHMDS(52.64 mL, 55.8 mmol) was added dropwise from the dropping funnel.Following this addition, the reaction mixture was allowed to warm toroom temperature and stirred for a further 15 hours. The reactionsolvent was removed under reduced pressure and the resulting residuepartitioned between 1 M HCl (100 mL) and EtOAc (2×100 mL). The combinedEtOAc fractions were then washed with water (100 mL) and saturated NaCl(100 mL), dried (Na₂SO₄), and the EtOAc removed under reduced pressureto afford a crude product which was purified by chromatography on flashsilica (10% EtOAc/hexanes as eluant), giving the desired product as apale yellow solid (3.99 g, 59%); m.p. (EtOAc/hexanes) 164–167° C. ¹H NMR[400 MHz, (CD₃)₂SO] δ 13.70 (br s, 1 H), 9.31 (br s, 1 H), 7.82 (ddd,J=9.1, 6.1, 2.0 Hz, 1 H), 7.34 (dd, J=12.0, 1.9 Hz, 1 H), 7.18 (ddd,J=8.3, 1.9, 0.8 Hz, 1 H), 7.16 (td, J=9.5, 7.3 Hz, 1 H), 6.93 (ddd,J=8.9, 8.3, 5.4 Hz, 1 H), 0.22 (s, 9 H). Anal. Calcd for C₁₈H₁₆F₃NO₂Si:C, 59.5; H, 4.4; N, 3.9. Found: C, 59.7; H, 4.7; N, 3.9.

Step C: Preparation of3,4-difluoro-2-[(4-ethynyl-2-fluorophenyl)amino]benzoic acid

The product of Step B,3,4-difluoro-2-[[2-fluoro-4-(trimethylsilylethynyl)phenyl]amino]benzoicacid (3.99 g, 11.0 mmol), was dissolved in MeOH (200 mL), to which wasadded K₂CO₃ (3.03 g, 22.0 mmol). This mixture was stirred at roomtemperature for 15 hours, then the reaction solvent removed underreduced pressure. The resulting residue was dissolved in water (50 mL),to which was added 1 M HCl until the pH=4. The resulting pale brownprecipitate was collected by filtration and dried to afford the desiredproduct (3.17 g, 99%); m.p. (EtOAc/hexanes) 160–162° C. ¹H NMR [400 MHz,(CD₃)₂SO] δ 13.70 (br s, 1 H), 9.24 (br s, 1 H), 7.82 (ddd, J=9.2, 6.1,2.1 Hz, 1 H), 7.38 (dd, J=12.0, 1.9, 1 H), 7.21 (ddd, J=8.4, 1.9, 0.8Hz, 1 H), 7.16 (td, J=9.5, 7.3 Hz, 1 H), 6.96 (ddd, J=8.9, 8.4, 5.4 Hz,1 H), 4.15 (s, 1 H). Anal. Calcd for C₁₅H₈F₃NO₂: C, 62.4; H, 3.1; N,4.7. Found: C, 62.4; H, 3.2; N, 4.6.

Step D: Preparation of2-[(4-ethyl-2-fluorophenyl)amino]-3,4-difluorobenzoic acid

The product of Step C,3,4-difluoro-2-[(4-ethynyl-2-fluorophenyl)amino]benzoic acid (300 mg,1.03 mmol), was dissolved in absolute ethanol (30 mL) and 5% Pd/C (30mg) added. This mixture was stirred under an atmosphere of hydrogen (60psi) for 2 hours at room temperature. The Pd/C was removed over Celite®,which was washed well with additional ethanol, then the solvent removedfrom the resultant filtrate under reduced pressure to afford2-[(4-ethyl-2-fluorophenyl)amino]-3,4-difluorobenzoic acid as anoff-white solid (280 mg, 92%); m.p. (EtOAc/hexanes) 199–201° C. ¹H NMR[400 MHz, (CD₃)₂SO] δ 14.10 (br s, 1 H), 9.31 (br s, 1 H), 7.80 (ddd,J=8.5, 6.1, 1.9 Hz, 1 H), 7.09 (dd, J=12.4, 1.5 Hz, 1 H), 7.04–6.92 (m,3 H), 2.52 (q, J=7.6 Hz, 2 H), 1.17 (t, J=7.5 Hz, 3 H).

Step E: Preparation of2-[(4-ethyl-2-fluorophenyl)amino]-3,4-difluoro-N-(2-hydroxyethoxy)benzamide

The title compound was prepared from the reaction of the product of StepD, 2-[(4-ethyl-2-fluorophenyl)amino]-3,4-difluorobenzoic acid (93 mg,0.32 mmol) dissolved in dry THF (5 mL), and carbonyldiimidazole (CDI)(102 mg, 0.63 mmol). Within 10 minutes, a bright yellow solution wasobtained and conversion to the imidazolide was confirmed by TLC (50%EtOAc/hexanes). A solution of 2-(aminooxy)ethanol (97 mg, 1.26 mmol) inTHF (5 mL) was then added and the mixture stirred for 15 hours at roomtemperature. The reaction solvent was removed under reduced pressure andthe residue partitioned between 1 M HCl (50 mL) and EtOAc (50 mL). TheEtOAc layer was then washed with water (50 mL) and saturated NaClsolution (50 mL), dried (Na₂SO₄), and the solvent removed under reducedpressure to afford an oil which was purified by flash columnchromatography on silica gel (50% EtOAc/hexanes) to give2-[(4-ethyl-2-fluorophenyl)amino]-3,4-difluoro-N-(2-hydroxyethoxy)benzamideas a cream solid (65%); m.p. (EtOAc/hexanes) 134–138° C. ¹H NMR [400MHz, (CD₃)₂SO] δ 11.84 (br s, 1 H), 8.76 (br s, 1 H), 7.43–7.37 (m, 1H), 7.14–7.02 (m, 2 H), 6.90 (dd, J=8.3, 1.5 Hz, 1 H), 6.83. (td, J=8.6,4.4 Hz, 1 H), 4.70 (br s, 1 H), 3.86 (t, J=4.9 Hz, 2 H), 3.57 (t, J=4.9Hz, 2 H), 2.54 (q, J=7.6 Hz, 2 H), 1.15 (t, J=7.6 Hz, 3 H).

EXAMPLE 2

2-(2-Chloro-4-ethyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide

Step A: Preparation of2-(2-chloro-4-iodophenylamino)-3,4-difluorobenzoic acid

To a solution of 2,3,4-trifluorobenzoic acid (75 g, 0.426 mol) inanhydrous tetrahydrofuran at −78° C. under nitrogen was added slowlylithium bis(trimethylsilyl)amide (426 mL, 0.426 mol, 1.0 M solution inTHF). The dark brown reaction mixture was stirred for 15 minutes at −65°C. (inside temp). This is referred to as Solution A.

To a solution of 2-chloro-4-iodoaniline (108 g, 0.426 mol) in anhydroustetrahydrofuran (1000 mL) at −78° C. (outside) under nitrogen was addedslowly lithium bis(trimethylsilyl)amide (852 mL, 0.852 mol, Aldrich, 1.0M solution in THF). The dark green solution was stirred for 0.5 hours.This is referred to as Solution B.

Solution A was transferred to Solution B using positive nitrogenpressure. The reaction mixture was stirred at ambient temperatureovernight. The reaction was quenched with 2.5 L dry ether (saturatedwith hydrogen chloride gas) until the pH was about 1.0. The precipitatedsolid was filtered off through Celite® and washed thoroughly with ether.

The filtrate was washed with 1N HCl (2×500 mL), brine (2×500 mL), driedand concentrated to give a light brown solid (143 g) which wascrystallized from methanol (450 mL) and methylene chloride (1.25 L) toafford 2-(2-chloro-4-iodophenylamino)-3,4-difluorobenzoic acid (104 g,60% yield) as an off-white powder: m.p. 226–227° C.; ¹H NMR (400 MHz,DMSO-d₆) δ 13.83 (br s), 9.26 (s), 7.85 (ddd, J=8.9, 6.1, 1.9 Hz, 1 H),7.81 (d, J=1.9 Hz, 1 H), 7.54 (dd, J=8.6, 1.9 Hz, 1 H), 7.18 (dt, J=7.3,9.3 Hz, 1 H), 6.74 (dd, J=8.5, 7.1 Hz, 1 H); ¹⁹F-NMR (376 MHz, DMSO-d₆)δ −129.9, −141.9. Anal. Calcd/found for C₁₃H₇NO₂F₂ClI: C, 38.13/37.33;H, 1.72/1.60; N, 3.42/3.31.

Step B: Preparation of2-(2-chloro-4-iodophenylamino)-3,4-difluorobenzoic acidPentafluorophenyl Ester

To a solution of the product of Example 2, Step A,2-(2-chloro-4-iodophenylamino)-3,4-difluorobenzoic acid (10.0 g, 24.4mmol), and pyridine (2.16 mL, 26.8 mmol) in anhydrous dimethylformamide(49 mL) was added pentafluorophenyl trifluoroacetate (5.35 mL, 30.5mmol). The resultant solution was stirred at ambient temperature for 2hours. The reaction mixture was diluted with ethyl acetate (600 mL) andwashed with 0.1 M aqueous hydrochloric acid (2×240 mL), 25% saturatedaqueous sodium bicarbonate (2×240 mL), and saturated brine (240 mL). Theorganics were dried over anhydrous magnesium sulfate and concentratedunder reduced pressure to afford an oil that was purified on silica gel.Elution with hexanes-ethyl acetate (19:1) afforded2-(2-chloro-4-iodophenylamino)-3,4-difluorobenzoic acidpentafluorophenyl ester (12.8 g, 91%) as a pale-yellow powder: m.p.108.5–110.0° C.; ¹H-NMR (400 MHz, CDCl₃) δ 8.77 (br s, 1 H), 8.07 (br s,1 H), 7.69 (br s, 1 H), 7.48 (br d, J=7.0 Hz, 1 H), 6.91 (br d, J=7.2Hz, 1 H), 6.67 (br s., 1 H); ¹⁹F-NMR (376 MHz, CDCl₃) δ −123.74 (s, 1F),−139.17 (d, J=16.8 Hz, 1F), −152.35 (d, J=21.4 Hz, 2F), −156.96 (t,J=21.4 Hz, 1F), −161.81 (t, J=21.4 Hz, 2F). Anal. Calcd/found forC₁₉H₆NO₂F₇ClI: C, 39.65/39.32; H, 1.05/0.91; N, 2.43/2.35; F,23.10/22.85; Cl, 6.16/6.92; I, 22.05/22.50.

Step C: Preparation of2-(2-chloro-4-iodo-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide

To a solution of the product of Example 2, Step B,2-(2-chloro-4-iodo-phenylamino)-3,4-difluorobenzoic acidpentafluorophenyl ester (10.0 g, 17.4 mmol), in anhydrousdimethylformamide (36 mL) was added 2-(aminooxy)-ethanol [prepared bythe literature procedure: Dhanak, D.; Reese, C. B., J. Chem. Soc.,Perkin Trans. 1987; 1:2829] (1.6 g, 20.8 mmol) andN,N-diisopropylethylamine (6.0 mL, 34.8 mmol). The resultant solutionwas stirred at ambient temperature for 16 hours. The reaction mixturewas concentrated to 20% volume then diluted with ethyl acetate (360 mL).The resultant solution was washed with water (6×60 mL) and brine (2×60mL). The organics were dried over anhydrous magnesium sulfate andconcentrated under reduced pressure to afford a white solid that waspurified on silica gel. Elution with ethyl acetate-methanol (9:1)afforded2-(2-chloro-4-iodo-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide(7.31 g, 90%) as a white solid. Recrystallization from methanol affordedanalytically pure material: m.p. 173–175° C.; ¹H NMR (400 MHz, DMSO-d₆)δ 11.93 (br s, 1 H), 8.85 (br s, 1 H), 7.76 (d, J=1.7 Hz, 1 H), 7.48(dd, J=8.6, 1.7 Hz, 1 H), 7.44 (dd, J=8.5, 6.2 Hz, 1 H), 7.25 (dt,J=8.5, 9.3 Hz, 1 H), 6.58 (dd, J=8.5, 6.4 Hz, 1 H), 4.70 (br s, 1 H),3.86 (br s, 2 H), 3.56 (br d, J=3.9 Hz, 2 H); MS (APCI+)=469.0; MS(APCI−)=467.0; Anal. Calcd/found for C₁₅H₁₂ClF₂₁N₂O₃: C, 38.45/38.60; H,2.58/2.53; N, 5.98/5.91; F, 8.11/8.08; I, 27.08/27.43.

Step D: Preparation of2-(2-chloro-4-vinyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide

A solution of the product of Example 2, Step C,2-(2-chloro-4-iodo-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide(2.00 g, 4.27 mmol), in 1,4-dioxane (30 mL) was twice deoxygenated usingthe freeze-pump-thaw technique and subsequently stirred at ambienttemperature under nitrogen. Tributyl(vinyl)tin (1.37 mL, 4.68 mmol) andtetrakis(triphenylphosphine)palladium (250 mg, 0.21 mmol) were added,and the reaction mixture was gradually warmed to 95° C. over 4 hours andwas stirred at 95° C. overnight under an atmosphere of nitrogen. Thereaction mixture was cooled to ambient temperature and filtered througha pad of Celite®, washing the filter cake with ethyl acetate (120 mL).The combined filtrate and washings were shaken with 1 M aqueouspotassium fluoride solution (25 mL). The aqueous salts were removed byfiltration and the organics were further washed with 1 M aqueouspotassium fluoride solution (25 mL), water (2×50 mL), and saturatedaqueous brine (50 mL). The organics were dried over anhydrous magnesiumsulfate and were concentrated under reduced pressure to afford a darkcolored oil that was purified by silica gel chromatography. Elution withethyl acetate afforded a yellow-colored foam (0.79 g) which wastriturated with ether/hexanes to afford2-(2-chloro-4-vinyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamideas a straw-colored solid (0.69 g, 44% yield): ¹H NMR (400 MHz, DMSO-d₆)δ 11.97 (br s, 1 H), 8.94 (br s, 1 H), 7.59 (d, J=1.7 Hz, 1 H), 7.47 (brt, J=6.4 Hz, 1 H), 7.31 (dd, J=8.3, 2.0 Hz, 1 H), 7.29–7.21 (m, 1 H),6.77 (dd, J=8.3, 6.6 Hz, 1 H), 6.64 (dd, J=17.6, 11.0 Hz, 1 H), 5.75(dd, J=17.6, 0.7 Hz, 1 H), 5.18 (dd, J=10.8, 0.7 Hz, 1 H), 4.73 (br s, 1H), 3.88 (br s, 2 H), 3.58 (br s, 2 H); ¹⁹F NMR (376 MHz, DMSO-d₆) δ−132.5, −141.3 (d, J=20.2 Hz); MS (APCI+)=368.9. Anal. Calcd/found forC₁₇H₁₅CtF₂N₂O₃: C, 55.37/55.46; H, 4.10/3.91; N, 7.60/7.37.

Step E: Preparation of2-(2-chloro-4-ethyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide

A solution of the product of Example 2, Step D,2-(2-chloro-4-vinyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide(0.291 g, 0.789 mmol) in tetrahydrofuran (16 mL) was hydrogenated over10% palladium on carbon (0.08 g) at 6900 psig at room temperature for 17hours. The catalyst was removed by filtration and the filtrate wasconcentrated in vacuo to afford a crystalline solid. The solid wasdissolved in methanol and concentrated to near dryness. Ether (10 mL)was added and the mixture was allowed to stand at ambient temperaturefor 6 hours. during which crystallization ensued. The white crystalswere filtered, washed with a small volume of ether, and dried in vacuoat 60° C. overnight yielding2-(2-chloro-4-ethyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide(222 mg): m.p. 142.5–145° C.; ¹H NMR (400 MHz, DMSO-d₆) δ 11.94 (br s, 1H), 8.85 (br s, 1 H), 7.44 (br t, J=6.4 Hz, 1 H), 7.30 (d, J=2.0 Hz, 1H), 7.22–7.15 (m, 1 H), 7.05 (dd, J=8.3, 2.0 Hz, 1 H), 6.75 (dd, J=8.3,6.3 Hz, 1 H), 4.71 (br s, 1 H), 3.89 (br s, 2 H), 3.59 (br s, 2 H), 2.54(q, J=7.6 Hz, 2 H), 1.15 (t, J=7.6 Hz, 3 H); ¹⁹F NMR (376 MHz, DMSO-d₆)δ −132.7, −142.0; MS (APCI+)=371.0. Anal. Calcd/found forC₁₇H₁₇ClF₂N₂O₃: C, 55.07/55.14; H, 4.62/4.51; N, 7.56/7.38; F,10.25/9.98.

EXAMPLE 3

3,4-Difluoro-2-(2-fluoro-4-methylanilino)-N-(2-hydroxyethoxy)benzamide

2,3,4-Trifluorobenzoic acid and 2-fluoro-4-methylaniline were reacted inthe presence of LiHMDS solution in THF by the general procedure ofExample 1, Step B. After workup,3,4-difluoro-2-[2-fluoro-4-methylanilino]benzoic acid was isolated as acrude pale brown solid which was reacted directly with2-(aminooxy)ethanol and DMT-MM by the general procedure of Example 6,Step B below, then purified by column chromatography on silica gel (100%EtOAc as eluant) to give3,4-difluoro-2-(2-fluoro-4-methylanilino)-N-(2-hydroxyethoxy)benzamideas a white solid (44%); m.p. (EtOAc/hexane) 134–139° C. ¹H NMR [400 MHz,(CD₃)₂SO] [ ] 11.82 (v br s, 1H), 8.77 (br s, 1 H), 7.41 (ddd, J=8.1,5.7, 1.6 Hz, 1 H), 7.13–7.00 (m, 2 H), 6.88 (dd, J=8.3, 1.1 Hz, 1 H),6.82 (ddd, J=8.5, 8.5, 4.2 Hz, 1 H), 4.76 (v br s, 1 H), 3.86 (t, J=5.0Hz, 2 H), 3.58 (J=5.0 Hz, 2 H), 2.25 (s, 3 H). Anal. calcd. forC₁₆H₁₅F₃N₂O₃: C, 56.5; H, 4.4; N, 8.2. Found C, 56.3; H, 4.5; N, 8.2.

EXAMPLE 4

3,4-Difluoro-2-[(2-fluoro-4-vinylphenyl)amino]-N-(2-hydroxyethoxy)benzamide

Step A: Preparation of3,4-difluoro-2-[(2-fluoro-4-vinylphenyl)amino]benzoic acid

The product of Example 1, Step C,2-[(4-ethynyl-2-fluorophenyl)amino]-3,4-difluorobenzoic acid (540 mg,1.86 mmol) and quinoline (220 mg) were dissolved in THF (50 mL), thenLindlar catalyst (11 mg) added. This mixture was stirred under anatmosphere of hydrogen (60 psi) for 3 periods of 15 minutes andmonitored carefully by TLC (50% EtOAc/hexanes as eluant). The reactionmixture was filtered through Celite® which was washed well with EtOAcand the resulting filtrate concentrated (to 100 mL) under reducedpressure. This organic solution was then washed with 1 M HCl (2×100 mL),water (100 mL) and saturated NaCl solution (100 mL), dried (Na₂SO₄), andthe solvent removed under reduced pressure. The resulting crude solidwas purified by flash chromatography on silica (10% EtOAc/hexanes aseluant) to afford 3,4-difluoro-2-[(2-fluoro-4-vinylphenyl)amino]benzoicacid as a crystalline yellow solid (390 mg, 72%); m.p. (EtOAc/hexanes)162–166° C. ¹H NMR [400 MHz, (CD₃)₂SO] δ 13.20 (br s, 1 H), 9.30 (br s,1 H), 7.52 (ddd, J=8.3, 6.1, 1.8 Hz, 1 H), 7.41 (dd, J=12.8, 1.7 Hz, 1H), 7.19 (dd, J=8.3, 1.7 Hz, 1 H), 7.08 (dd, J=16.6, 9.3 Hz, 1 H), 7.00(td, J=8.7, 5.2 Hz, 1 H), 6.67 (dd, J=17.6, 10.9 Hz, 1 H), 5.78 (d,J=17.6 Hz, 1 H), 5.22 (d, J=11.0 Hz, 1 H). Anal. Calcd for C₁₅H₁₀F₃NO₂:C, 61.4; H, 3.3; N, 4.9. Found C, 61.4; H, 3.4; N, 4.8.

Step B: Preparation of3,4-difluoro-2-[(2-fluoro-4-vinylphenyl)amino]-N-(2-hydroxyethoxy)benzamide

The title compound was prepared from reaction of the product of Example4, Step A, 3,4-difluoro-2-[(2-fluoro-4-vinylphenyl)amino]benzoic acidwith CDI and 2-(aminooxy)ethanol by the general procedure of Example 1,Step E, then purified by flash column chromatography on silica gel (10%EtOAc/hexanes) to give3,4-difluoro-2-[(2-fluoro-4-vinylphenyl)amino]-N-(2-hydroxyethoxy)benzamideas a crystalline white solid (78%); m.p. (EtOAc/hexanes) 134–138° C. ¹HNMR [400 MHz, (CD₃)₂SO] δ 11.85 (br s, 1 H), 8.82 (br s, 1 H), 7.45–7.38(m, 1 H), 7.37 (dd, J=12.9, 1.8 Hz, 1 H), 7.21–7.15 (m, 1 H), 7.14 (dd,J=8.4, 1.7 Hz, 1 H), 6.83 (td, J=8.7, 4.8 Hz, 1 H), 6.65 (dd, J=17.6,10.8 Hz, 1 H), 5.73 (d, J=17.9 Hz, 1 H), 5.18 (d, J=11.1 Hz, 1 H), 4.70(br s, 1 H), 3.85 (t, J=4.8 Hz, 1 H), 3.56 (t, J=4.8 Hz, 2 H). Anal.Calcd for C₁₇H₁₅F₃N₂O₃: C, 58.0; H, 4.3; N, 8.0. Found C, 57.6; H, 4.6;N, 8.1.

EXAMPLE 4A

2-[(4-vinyl-2-fluorophenyl)amino]-3,4-difluoro-N-(2-hydroxy-ethoxy)benzamideStep A: Preparation of Vinylboronic Acid

In a three-necked, round-bottomed flask equipped with a low temperaturethermometer and magnetic stirrer under nitrogen was placed a solution oftrimethyl borate (10 ml, 89.2 mmol) in dry THF (75 ml). The contents ofthe flask were cooled to −70° C. and a 1 M solution of vinylmagnesiumbromide (50 ml, 50 mmol) was added dropwise over 50 minutes. Theresulting solution was stirred at this temperature for an additionalhour and then quenched with 1 N HCl (25 ml). The contents of the flaskwere allowed to warm up to ambient temperature and brine (50 ml) wasadded. The aqueous phase was extracted with diethyl ether (2×100 ml) andthe combined organic extracts were washed with water (50 ml), brine (50ml) and dried over MgSO₄. The solvent was evaporated under vacuum to afinal volume of, approximately, 25 ml and this solution of vinylboronicacid was used without any further purification for the next step.

Step B: Preparation of Boron Complex 2

To the solution obtained in the previous step was added dry pyridine (10ml) and the resulting mixture was stirred at ambient temperature for 18h. The solvent was removed under vacuum and the clear, oily residue wasdistilled to give 3.00 g (42% yield) of a clear oil 2 (bp 50–52° C., 0.1mm of Hg) which, after being placed in a freezer at −24° C. overnight,turned into a white solid. ¹H NMR (CDCl₃): δ 5.75–5.79 (m, 3 H),5.91–5.99 (m, 6 H), 7.58–7.62 (m, 2 H), 7.99–8.03 (m, 1 H), 8.79–8.81(m, 2 H).

Step C: Preparation of2-[(4-vinyl-2-fluorophenyl)amino]-3,4-difluoro-N-(2-hydroxy-ethoxy)benzamide

3,4-difluoro-2-(2-fluoro-4-iodo-phenylamino)-N-(2-hydroxy-ethoxy)-benzamide(1.00 g, 2.21 mmol) was dissolved in dry dimethoxyethane (DME, 18 ml)under a nitrogen atmosphere, Pd(Ph₃P)₄ (0.13 g, 0.11 mmol) was added andthe resulting yellow solution was stirred at ambient temperature for 20min. K₂CO₃ (−325 mesh, 0.31 g, 2.21 mmol), water (5.3 ml) and boroncomplex 2 (0.54 g, 2.21 mmol) were added and the contents of the flaskwere refluxed for 1 h.¹ Water (50 ml) and brine (50 ml) were added andthe aqueous phase was extracted with ethyl acetate (3×50 ml). Thecombined organic extracts were washed with brine (20 ml) and dried overMgSO₄. The solvent was removed under vacuum and the residual dark orangeoil was chromatographed (ethyl acetate as eluent) to give 0.59 g (76%yield) of2-[(4-vinyl-2-fluorophenyl)amino]-3,4-difluoro-N-(2-hydroxy-ethoxy)benzamideas a light yellow solid, mp 134–137° C. ¹H NMR (d₆-DMSO) δ 3.53–3.54 (m,2 H), 3.82 (s, 2 H), 4.69–4.72 (m, 1 H), 5.14 (d, 1H, J=11 Hz),5.69–5.77 (m, 1 H), 6.57–6.64 (m, 1 H), 6.77–6.83 (m, 1 H), 7.09–7.18(m, 2 H), 7.33–7.40 (m, 2 H), 8.74 (bs, 1 H), 11.86 (bs, 1 H).

A small sample was recrystallized from hexanes/ethyl acetate andsubmitted for elemental analysis. The results are as follows: C, 57.81(57.96); H, 4.38 (4.29); N, 7.56 (7.95); F, 16.02 (16.28).

EXAMPLE 5

2-(2-Chloro-4-vinyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide

The title compound can be prepared by the procedure of Example 2, StepsA–D (0.69 g, 44% yield): ¹H NMR (400 MHz, DMSO-d₆) δ 11.97 (br s, 1 H),8.94 (br s, 1 H), 7.59 (d, J=1.7 Hz, 1 H), 7.47 (br t, J=6.4 Hz, 1 H),7.31 (dd, J=8.3, 2.0 Hz, 1 H), 7.29–7.21 (m, 1 H), 6.77 (dd, J=8.3, 6.6Hz, 1 H), 6.64 (dd, J=17.6, 11.0 Hz, 1 H), 5.75 (dd, J=17.6, 0.7 Hz, 1H), 5.18 (dd, J=10.8, 0.7 Hz, 1 H), 4.73 (br s, 1 H), 3.88 (br s, 2 H),3.58 (br s, 2 H); ¹⁹F NMR (376 MHz, DMSO-d₆) δ −132.5, −141.3 (d, J=20.2Hz); MS (APCI+)=368.9. Anal. Calcd/found for C₁₇H₁₅ClF₂N₂O₃: C,55.37/55.46; H, 4.10/3.91; N, 7.60/7.37.

EXAMPLE 6

2-(4-Allyl-2-fluoroanilino)-3,4-difluoro-N-(2-hydroxyethoxy)benzamide

Step A: Preparation of methyl3,4-difluoro-2-(2-fluoro-4-iodoanilino)-3,4-difluorobenzoate

2-(2-Fluoro-4-iodoanilino)-3,4-difluorobenzoic acid (which can beprepared according to the procedure in PCT publication No. WO 00/41505)(5.00 g, 12.7 mmol) was dissolved in a mixture of Et₂O (60 mL) and MeOH(30 mL), then TMS-diazomethane solution (8.27 ml of a 2 M solution inhexanes, 16.5 mmol) was added dropwise. This mixture was stirred at RTfor 15 h., the excess reagent quenched with acetic acid, then allsolvents removed under reduced pressure. The resulting residue wasdissolved in EtOAc (200 mL), which was washed with saturated NaHCO₃(2×200 mL), water (200 mL) and brine (100 mL). The EtOAc layer was thendried (Na₂SO₄) and the solvent removed under reduced pressure to affordmethyl 3,4-difluoro-2-(2-fluoro-4-iodoanilino)-3,4-difluorobenzoate as apink solid (5.16 g, 100%) which was used directly in the next step. ¹HNMR [400 MHz, (CD₃)₂SO] δ 8.73 (s, 1 H), 7.76 (ddd, J=9.0, 6.0, 2.1 Hz,1 H), 7.61 (dd, J=10.8, 1.9 Hz, 1 H), 7.41 (ddd, J=8.5, 1.9, 1.0 Hz, 1H), 7.21–7.12 (m, 1 H), 6.80 (ddd, J=8.8, 8.8, 4.4 Hz, 1 H), 3.81 (s,3H).

Step B: Preparation of 2-(4-Allyl-2-fluoroanilino)-3,4-difluorobenzoicacid

Methyl 3,4-difluoro-2-(2-fluoro-4-iodoanilino)benzoate (1.00 g), 2.45mmol) and (Ph₃P)₄Pd (568 mg, 0.49 mmol) were weighed into a dry flaskwhich was fitted with a condensor and flushed with nitrogen. Dioxane (20mL) and allyltributyltin (976 mg, 2.95 mmol) were added via syringe andthe entire mixture heated at reflux overnight. All solvent was removedunder reduced pressure and the residue loaded directly onto a silica gelcolumn (10% EtOAc/PE as eluant). After chromatography, the crude methylester was obtained as a pale yellow oil which was dissolved in a mixtureof EtOH (25 mL) and 1 M NaOH (25 mL) and stirred overnight at RT. Themixture was then diluted with water (70 mL) and acidified with 1 M HCl(approx. 30 mL), then extracted with EtOAc (3×100 mL). The combinedEtOAc fractions were washed with water (100 mL), brine (100 mL), dried(Na₂SO₄), then the solvent removed under reduced pressure to afford apale yellow solid which was purified by chromatography on silica gel(50% EtOAc/PE as eluant) to afford2-(4-allyl-2-fluoroanilino)-3,4-difluorobenzoic acid as pale yellowneedles (583 mg, 72%); m.p. (EtOAc/hexane) 199–201° C. ¹H NMR [400 MHz,(CD₃)₂SO] δ 13.68 (v br s, 1 H), 9.25 (br s, 1 H), 7.81 (ddd, J=8.3,6.1, 2.0 Hz, 1 H), 7.07 (dd, J=12.2, 1.7 Hz, 1 H), 7.06–6.98 (m, 2 H),6.93 (dd, J=8.2, 1.6 Hz, 1 H), 6.01–5.89 (m, 1 H), 5.13–5.03 (m, 2 H),3.51–3.40 (m, 2H, obscured by H₂O). Anal. calcd. for C₁₆H₁₂F₃NO₂: C,62.5; H, 3.9; N, 4.6. Found C, 62.7; H, 4.1; N, 4.5.

Step C: Preparation of2-(4-allyl-2-fluoroanilino)-3,4-difluoro-N-(2-hydroxyethoxy)benzamide

2-(4-Allyl-2-fluoroanilino)-3,4-difluorobenzoic acid (700 mg, 2.28 mmol)was dissolved in MeOH (20 mL) to which was added 2-(aminooxy)ethanol(263 mg, 3.42 mmol), followed by4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methymorpholinium chloride[DMT-MM, prepared according to the procedure of Kunishima et al[Tetrahedron, 55, 13159–13170 (1999)]] (946 mg, 3.42 mmol). This mixturewas stirred 15 h. at room temperature. The MeOH was removed underreduced pressure and the resulting oil dissolved in EtOAc (100 mL),which was washed with water (2×100 mL), brine (100 mL) and dried(Na₂SO₄). The solvent was removed under reduced pressure to afford acrude yellow oil which was purified by filtration through a plug ofsilica gel (50% EtOAc/PE as eluant) to give2-(4-allyl-2-fluoroanilino)-3,4-difluoro-N-(2-hydroxyethoxy)benzamide asa white solid (734 mg, 88%); m.p. (EtOAc/hexane) 173–177° C. ¹H NMR [400MHz, (CD₃)₂SO] δ 11.85 (br s, 1 H), 8.75 (br s, 1 H), 7.43–7.37 (m, 1H), 7.14–7.07 (m, 1 H), 7.05–6.99 (m, 1 H), 6.90–6.81 (m, 2 H),5.99–5.87 (m, 1 H), 5.02–5.11 (m, 2 H), 4.70 (br s, 1 H), 3.85 (t, J=4.9Hz, 1H), 3.57 (t, J=4.9 Hz, 1 H), 3.51–3.40 (m, 2H, obscured by H₂O).Anal. calcd. for C₁₈H₁₇F₃N₂O₃: C, 59.0; H, 4.7; N, 7.7. Found C, 59.1;H, 4.5; N, 7.4.

EXAMPLE 7

2-[(4-Ethynyl-2-fluorophenyl)amino]-3,4-difluoro-N-2-hydroxyethoxy)benzamide

The product of Example 1, Step C,3,4-difluoro-2-[(4-ethynyl-2-fluorophenyl)amino]benzoic acid (349 mg,1.20 mmol) was dissolved in dry THF (15 mL), to which was addedcarbonyldiimidazole (CDI) (389 mg, 2.40 mmol). Within 10 minutes, abright yellow solution was obtained and conversion to the imidazolidewas confirmed by TLC (50% EtOAc/hexanes). A solution of2-(aminooxy)ethanol (370 mg, 4.80 mmol) in THF (5 mL) was then added andthe mixture stirred for 15 hours at room temperature. The reactionsolvent was removed under reduced pressure and the residue partitionedbetween 1 M HCl (100 mL) and EtOAc (100 nL). The EtOAc layer was thenwashed with water (100 mL) and saturated NaCl solution (100 mL), dried(Na₂SO₄), and the solvent removed under reduced pressure to afford anoil which was purified by flash column chromatography on silica gel (50%EtOAc/hexanes) to give2-[(4-ethynyl-2-fluorophenyl)amino]-3,4-difluoro-N-(2-hydroxyethoxy)benzamideas a pale yellow solid (232 mg, 55%); m.p. (EtOAc/hexanes) 158–161° C.¹H NMR [400 MHz, (CD₃)₂SO] δ 11.80 (br s, 1 H), 8.84 (br s, 1 H), 7.43(ddd, J=8.8, 5.9, 1.9 Hz, 1 H), 7.34 (dd, J=12.2, 1.9 Hz, 1 H), 7.25(ddd, J=9.9, 9.0, 7.3 Hz, 1 H), 7.16 (ddd, J=8.3, 1.9, 0.9 Hz, 1 H),6.79 (ddd, J=9.1, 8.3, 4.9 Hz, 1 H), 4.71 (br s, 1 H), 4.10 (s, 1 H),3.84 (t, J=5.0 Hz, 2 H), 3.56 (t, J=5.0 Hz, 2 H). Anal. Calcd forC₁₇H₁₃F₃N₂O₃: C, 58.5; H, 4.1; N, 8.0. Found: C, 58.3; H, 3.7; N, 8.0.

EXAMPLE 7A

2-[(4-ethynyl-2-fluorophenyl)amino]-3,4-difluoro-N-(2-hydroxy-ethoxy)benzamide

Step A: Preparation of2-[(4-(2-trimethylsilyl)ethynyl-2-fluorophenyl)amino]-3,4-difluoro-N-(2-hydroxyethoxy)benzamide

A 1 L round-bottomed flask was charged with compound3,4-difluoro-2-(2-fluoro-4-iodo-phenylamino)-N-(2-hydroxy-ethoxy)-benzamide(45.2 g, 0.1 M) and PdCl₂(PPh₃)₂ (1.4 g, 2.0 mmol, 0.02 eq) and flushedwith argon gas. Trimethylsilyl-acetylene (15.5 mL, 0.11 mole, 1.1 eq.)was added, followed by the addition of Et₃N (250 mL). The mixture wasstirred under argon at ambient temperature for 15 minutes. Solid CuI(0.38 g, 2.0 mmol, 0.02 eq.) was added. The orange mixture was stirredat RT overnight (18 hrs). The reaction mixture turned dark brown. Thehigh performance liquid chromatography (HPLC) test of an aliquot showed99% of product and no starting material. The mixture was concentratedunder reduced pressure. Water (100 mL) was added and the mixture wasacidified to pH ˜1 with 1N HCl. The mixture was extracted with EtOAc(3×100 mL). The combined organic extracts were washed with brine,saturated NaHCO₃, and dried (MgSO₄). The solvent was evaporated undervacuo to give a brown solid, which was stirred inheptane-dichloromethane (1:1, 200 mL) for 15 min. The solid (most of thebrown impurities were washed out with this trituration.) was filtered,and recrystallized from heptane-EtOAc (Decolorizing charcoal was used toremove yellow color. If charcoal was not used, the product wasoff-white.) to give white solid. The solid was dried at 50° C. vacuumoven for 20 hrs to yield2-[(4-(2-trimethylsilyl)ethynyl-2-fluorophenyl)amino]-3,4-difluoro-N-(2-hydroxyethoxy)benzamideas a white solid, 33.9 g, 80.4%, mp 178–178.5° C., Anal.: C, 56.86(56.86); H, 5.11 (5.01); N, 6.61 (6.63); F, 13.62 (13.49).

Step B: Preparation of2-[(4-ethynyl-2-fluorophenyl)amino]-3,4-difluoro-N-(2-hydroxy-ethoxy)benzamide

A 0.5 L round-bottomed flask was charged with compound2-[(4-(2-trimethylsilyl)ethynyl-2-fluorophenyl)amino]-3,4-difluoro-N-(2-hydroxyethoxy)benzamide(10.2 g, 24.14 mmol) and anhydrous MeOH (200 mL). Powder K₂CO₃ (6.7 g,48.29 mmol, 2.0 eq.) was added. The white suspension was stirred atambient temperature for 5 hrs. Two thirds of MeOH was evaporated underreduced pressure. Water (300 mL) was added to the mixture. The mixturewas acidified to pH ˜1 with slow addition of 1N HCl. White solid formed.The mixture was stirred for 15 min. The solid was filtered washed withwater, and dried at 50° C. vacuum oven for 18 hrs. The solid wasrecrystallized from heptane-EtOAc (Decolorizing carbon was used. Withoutcharcoal, the product obtained was light yellow.) to give white solid.The solid was dried at 50° C. vacuum oven for 20 hrs to yield2-[(4-ethynyl-2-fluorophenyl)amino]-3,4-difluoro-N-(2-hydroxy-ethoxy)benzamideas a white solid, 7.9 g, 93.8%, mp 161.5–162.5° C., Anal.: C, 58.19(58.29); H, 3.59 (3.74); N, 7.81 (8.00); F, 16.34 (16.27).

EXAMPLE 7B

2-[(4-ethyl-2-fluorophenyl)amino]-3,4-difluoro-N-(2-hydroxyethoxy)-benzamide

A mixture of the product of Example 7A,2-[(4-ethynyl-2-fluorophenyl)amino]-3,4-difluoro-N-(2-hydroxy-ethoxy)benzamide(11.0 g, 31.40 mmol), Pd—C (10%, 1.0 g) in THF (100 mL) and MeOH (100mL) was subject to hydrogenation (25 psi) for 14.8 hrs (The reaction wasfollowed by HPLC until all SM peak disappeared.). The mixture wasfiltered through Celite® and the filtrates were concentrated to give alight yellow solid. The solid was recrystallized from heptane-EtOAc togive the title compound as a white solid, 6.97 g, 62.8%, mp 112–112.5°C. Anal.: C, 58.00 (57.63); H, 4.99 (4.84); N, 7.59 (7.91); F, 15.55(16.09).

EXAMPLE 8

2-(2-Chloro-4-ethynyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamideStep A: Preparation of2-(2-chloro-4-trimethylsilanylethynyl-phenylamino)-3,4difluoro-N-(2-hydroxy-ethoxy)-benzamide

The product of Example 2, Step C,2-(2-chloro-4-iodo-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide(3.25 g, 6.93 mmol) and (trimethylsilyl)acetylene (1.10 mL, 7.78 mmol)were combined in triethylamine (17 mL).Dichlorobis(triphenylphosphine)-palladium(II) (0.120 g, 0.017 mol) andcuprous iodide (0.033 g, 0.17 mmol) were added and the resultantsolution was stirred at ambient temperature for 22 hours. The reactionmixture was adsorbed onto Celite® for 20 min and was filtered, washingwith ethyl acetate. The filtrate was concentrated to a thick oil,further diluted with ethyl acetate (100 mL) and washed with aqueouscitric acid (2 M, 2×25 mL), water, and brine. The organic layer was thendried over magnesium sulfate and concentrated in vacuo to afford atan-colored solid. Recrystallization from heptane-ethyl acetate afforded2-(2-chloro-4-trimethylsilanylethynyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide(2.34 g, 76% yield) as a grey-colored solid: ¹H NMR (400 MHz, DMSO-d₆) δ11.96 (s, 1 H), 8.95 (s, 1 H), 7.53 (d, J=1.7 Hz, 1 H), 7.47 (m, 1 H),7.32 (m, 1 H), 7.27 -(dd, J=8.4, 1.8 Hz, 1 H), 6.72 (dd, J=8.0, 6.6 Hz,1 H), 4.73 (t, J=5.5 Hz, 1 H), 3.87 (apparent t, J=4.7 Hz, 2 H), 3.57(m, 2 H), 0.21 (s, 9 H); MS (APCI+)=439.1; MS (APCI−)=437.1.

Step B: Preparation of2-(2-chloro-4-ethynyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide

To a solution of the product of Example 8, Step A,2-(2-Chloro-4-trimethylsilanylethynyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide(0.704 g, 1.60 mmol) in methanol (21 mL) was added acetic acid (0.1 mL)and cesium fluoride (0.600 g, 3.95 mmol). The resultant solution wasstirred at ambient temperature. After 26 hours, the reaction mixture waspartitioned between ethyl acetate (100 mL) and water (25 mL) and theorganic layer was further washed with water (25 mL) and saturated brine(25 mL). The combined aqueous was extracted with ethyl acetate (50 mL).The combined organics were dried over magnesium sulfate and concentratedto a dark brown oil. Ether (15 mL) was added and crystallization ensued.The cream-colored solid was collected and dried under vacuum at 70° C.to afford2-(2-chloro-4-ethynyl-phenylamino)-3,4-difluoro-N-(2-hydroxy-ethoxy)-benzamide(0.290 g): m.p. 155–157° C.; ¹H NMR (400 MHz, DMSO-d₆) δ 11.94 (br s, 1H), 8.95 (br s, 1 H), 7.55 (d, J=2.0 Hz, 1 H), 7,48 (m, 1H), 7.34–7.27(m, 2 H), 6.74 (dd, J=8.4, 6.5 Hz, 1 H), 4.71 (br s, 1 H), 4.13 (s, 1H), 3.88 (t, J=4.6 Hz, 2 H), 3.58 (t, J=4.7 Hz, 2 H); MS (APCI+)=367.0;MS (APCI−)=365.0; Anal. Calcd/found for C₁₇H₁₃ClF₂N₂O₃: C, 55.67/55.54;H, 3.57/3.23; N, 7.64/7.31. Concentration of the mother liquor affordedan additional crop of product (0.209 g, 85% total yield).

EXAMPLE 9

2-[4-(3-Amino-1-propynyl)-2-fluoroanilino]-3,4-difluoro-N-(2-hydroxyethoxy)benzamide

The title compound was prepared by Sonogashira reaction of propargylamine and3,4-difluoro-2-(2-fluoro-4-iodo-phenylamino)-N-(2-hydroxy-ethoxy)-benzamideby the general procedure of Example 1, Step A. The orange oil resultingfrom workup was purified by chromatography on silica gel (10%MeOH/CH₂Cl₂ as eluant), to give2-[4-(3-amino-1-propynyl)-2-fluoroanilino]-3,4-difluoro-N-(2-hydroxyethoxy)benzamideas a pale orange solid (100%); m.p. (Et₂O) 72–76° C. ¹H NMR [400 MHz,(CD₃)₂SO] δ 9.14 (v br s, 1 H), 7.49–7.44 (m, 1 H), 7.21 (dd, J=12.3,1.7 Hz, 1 H), 7.24–7.14 (m, 1 H), 7.08 (dd, J=8.4, 1.6 Hz, 1 H), 6.77(ddd, J=8.8, 8.8, 5.1 Hz, 1 H), 5.45 (br s, 2 H), 3.83 (t, J=4.8 Hz, 2H), 3.55 (t, J=5.0 Hz, 2H), 3.41–3.32 (m, 2H, obscured by H₂O). Not allexchangeable protons observed. CRL10671. Await HRMS. Anal. calcd. forC₂₈H₁₆F₃N₃O₃: C, 57.0; H, 4.3; N, 11.1. Await Found. HRMS (EI⁺) calcdfor C₁₈H₁₆F₃N₃O₃ 379.1144 (M+), found 379.1140.

EXAMPLE 10

3,4-Difluoro-2-[2-fluoro-4-(3-hydroxy-1-propynyl)anilino]-N-(2-hydroxyethoxy)benzamide

Step A: Preparation of2-fluoro-4-[3-(tetrahydro-2H-pyran-2-yloxy)-1-propnyl]aniline

2-Propynyl tetrahydro-2H-pyran-2-yl ether was prepared according themethod of Li et al [J. Am Chem. Soc., 121(39), 9034–9042 (1999)].2-Fluoro-4-[3-(tetrahydro-2H-pyran-2-yloxy)-1-propynyl]aniline was thenprepared by Sonogashira reaction of 2-propynyl tetrahydro-2H-pyran-2-ylether and 2-fluoro-4-iodoaniline by the general procedure of Example 1,Step A. The desired product was isolated as an amber oil (91%). ¹H NMR[400 MHz, (CD₃)₂SO] δ 7.07 (dd, J=12.1, 1.8 Hz, 1 H), 6.98 (dd, J=8.2,1.7 Hz, 1 H), 6.70 (dd, J=9.3, 8.3 Hz, 1 H), 5.56 (br s, 2 H), 4.78 (brs, 1 H), 4.42 (d, J=15.9 Hz, 1 H), 4.33 (d, J=15.9 Hz, 1 H), 3.78–3.70(m, 2 H), 3.50–3.43 (m, 2 H), 1.77–1.59 (m, 2 H), 1.56–1.41 (m, 4 H).HRMS (EI⁺) calcd. for C₁₄H₁₆FNO₂ 249.1165 (M⁺), found 249.1164.

Step B: Preparation of3,4-difluoro-2-{2-fluoro-4-[3-(tetrahydro-2H-pyran-2-yloxy)-1-propynyl]anilino}benzoicacid

2,3,4-Trifluorobenzoic acid and2-fluoro-4-[3-(tetrahydro-2H-pyran-2-yloxy)-1-propynyl]aniline werereacted in the presence of LiHMDS solution in THF by the generalprocedure of Example 1, Step B. After workup, followed by purificationby chromatography on silica gel (50% EtOAc/PE as eluant),3,4-difluoro-2-{2-fluoro-4-[3-(tetrahydro-2H-pyran-2-yloxy)-1-propynyl]anilino}benzoicacid was isolated as a cream-yellow solid (68%); m.p. (Et₂O/hexane)164–166° C. ¹H NMR [400 MHz, (CD₃)₂SO] δ 13.60 (v br s, 1 H), 9.27 (brs, 1 H), 7.83 (ddd, J=8.2, 6.1, 1.9 Hz, 1 H), 7.36 (dd, J=12.0, 1.7 Hz,1 H), 7.21–7.11 (m, 2 H), 6.96 (td, J=8.8, 5.5 Hz, 1 H), 4.80 (br s, 1H), 4.47 (d, J=16.0 Hz, 1 H), 4.38 (d, J=16.0 Hz, 1 H), 3.79–3.71 (m,2H), 3.51–3.45 (m, 2 H), 1.77–1.61 (m, 2 H), 1.56–1.44 (m, 4 H). Anal.calcd. for C₂₁H₁₈F₃NO₄: C, 62.2; H, 4.5; N, 3.5. Found C, 62.5; H, 4.4;N, 3.6.

Step C: Preparation of3,4-difluoro-2-{2-fluoro-4-[3-(tetrahydro-2H-pyran-2-yloxy)-1-propynyl]anilino}-N-(2-hydroxyethoxy)benzamide

The title compound was prepared from reaction of3,4-difluoro-2-{2-fluoro-4-[3-(tetrahydro-2H-pyran-2-yloxy)-1-propynyl]anilino}benzoicacid with CDI and 2-(aminooxy)ethanol by the general procedure ofExample 1, Step E, then purified by column chromatography on silica gel(50% EtOAc/PE) as eluant), to give3,4-difluoro-2-{2-fluoro-4-[3-(tetrahydro-2H-pyran-2-yloxy)-1-propynyl]anilino}-N-(2-hydroxyethoxy)benzamideas a white solid (69%) which was used directly in the next step. ¹H NMR[400 MHz, (CD₃)₂SO] δ 11.80 (br s, 1 H), 8.87 (br s, 1 H), 7.46–7.39 (m,1 H), 7.31 (dd, J=12.2, 1.8 Hz, 1 H), 7.28–7.20 (m, 1 H), 7.14 (dd,J=8.3, 1.6 Hz, 1 H), 6.79 (ddd, J=8.8, 8.8, 4.7 Hz, 1H), 4.80 (br s,1H), 4.46 (d, J=16.1 Hz, 1H), 4.36 (d, J=16.0 Hz, 1 H), 3.84 (t, J=4.8Hz, 2 H), 3.75 (ddd, J=11.5, 8.6, 3.3 Hz, 2 H), 3.55 (t, J=4.8 Hz, 2 H),3.51–3.44 (m, 2 H), 1.76–1.60 (m, 2 H), 1.55–1.42 (m, 4 H). HRMS (EI⁺)calcd. for C₂₃H₂₃F₃N₂O₅ 464.1559 (M⁺), found 464.1558.

Step D: Preparation of3,4-difluoro-2-[2-fluoro-4-(3-hydroxy-1-propynyl)anilino]-N-(2-hydroxyethoxy)benzamide

3,4-Difluoro-2-{2-fluoro-4-[3-(tetrahydro-2H-pyran-2-yloxy)-1-propynyl]anilino}-N-(2-hydroxyethoxy)benzamide(115 mg, 0.25 mmol) was dissolved in EtOH (4 mL) to which was added 1 MHCl (5 drops). This reaction mixture was stirred overnight at RT, thenthe mixture was diluted with water (50 mL) and extracted with EtOAc(4×30 mL). The combined EtOAc fractions were washed with water (2×20mL), brine (50 mL) and dried (Na₂SO₄) then the solvent removed underreduced pressure to afford a white solid which was purified byfiltration through a plug of silica gel (EtOAc as eluant) to afford3,4-difluoro-2-[2-fluoro-4-(3-hydroxy-1-propynyl)anilino]-N-(2-hydroxyethoxy)benzamideas a cream solid (94 mg, 100%); m.p. (Et₂O/hexane) 169–172° C. ¹H NMR[400 MHz, (CD₃)₂SO] δ 11.84 (br s, 1 H), 8.91 (br s, 1 H), 7.46–7.40 (m,1 H), 7.29–7.19 (m, 2 H), 7.10 (dd, J=8.3, 1.6 Hz, 1 H), 6.78 (ddd,J=8.9, 8.9, 4.8 Hz, 1 H), 5.29 (t, J=5.9 Hz, 1 H), 4.76 (br s, 1 H),4.27 (d, J=5.9 Hz, 2 H), 3.84 (t, J=4.8 Hz, 2 H), 3.56 (t, J=4.8 Hz, 2H). Anal. calcd. for C₁₈H₁₅F₃N₂O₄: C, 56.9; H, 4.0; N, 7.4. Found C,56.8; H, 4.0; N, 7.4.

EXAMPLE 11

3,4-Difluoro-2-[2-fluoro-4-(4-hydroxy-1-butynyl)anilino]-N-(2-hydroxyethoxy)benzamide

Step A: Preparation of2-fluoro-4-[4-(tetrahydro-2H-pyran-2-yloxy)-1-butynyl]aniline

3-Butynyl tetrahydro-2H-pyran-2-yl ether was prepared according to themethod of Li et al [J. Am Chem. Soc., 121(39), 9034–9042 (1999)].2-Fluoro-4-[4-(tetrahydro-2H-pyran-2-yloxy)-1-butynyl]aniline was thenprepared by Sonogashira reaction of 3-butynyl tetrahydro-2H-pyran-2-ylether and 2-fluoro-4-iodoaniline by the general procedure of Example 1,Step A. The desired product was isolated as an orange oil (100%). ¹H NMR[400 MHz, (CD₃)₂SO] δ 6.96 (dd, J=12.2, 1.7 Hz, 1 H), 6.90 (dd, J=8.2,1.8 Hz, 1 H), 6.67 (dd, J=9.4, 8.4 Hz, 1 H), 5.43–5.41 (m, 2 H),4.66–4.63 (m, 1 H), 3.82–3.67 (m, 2 H), 3.56–3.40 (m, 2 H), 2.62 (t,J=6.9 Hz, 2 H), 1.78–1.56 (m, 2 H), 1.54–1.39 (m, 4 H). HRMS (EI⁺)calcd. for C₁₅H₁₈FNO₂ 263.1322 (M⁺), found 263.1323.

Step B: Preparation of3,4-difluoro-2-{2-fluoro-4-[4-(tetrahydro-2H-pyran-2-yloxy)-1-butynyl]anilino}benzoicacid

2,3,4-Trifluorobenzoic acid and2-fluoro-4-[4-(tetrahydro-2H-pyran-2-yloxy)-1-butynyl]aniline werereacted in the presence of LiHMDS solution by the general procedure ofExample 1, Step B. After workup, followed by purification by columnchromatography on silica gel (50% EtOAc as eluant), unreacted aniline(26%), followed by3,4-difluoro-2-{2-fluoro-4-[4-(tetrahydro-2H-pyran-2-yloxy)-1-butynyl]anilino}benzoicacid (31%) were isolated; m.p. (Et₂O/hexane) 175–178° C. ¹H NMR [400MHz, (CD₃)₂SO] δ 13.55 (v br s, 1 H), 9.28 (br s, 1 H), 7.82 (ddd,J=8.2, 6.0, 1.8 Hz, 1 H), 7.25 (dd, J=12.0, 1.7 Hz, 1 H), 7.16–7.08 (m,2 H), 6.95 (ddd, J=8.8, 8.8, 5.4 Hz, 1 H), 4.66 (t, J=3.4 Hz, 1 H),3.83–3.70 (m, 2 H), 3.59–3.41 (m, 2H), 2.68 (t, J=6.8 Hz, 1 H),1.78–1.58 (m, 2 H), 1.53–1.40 (m, 4 H). Anal. calcd. for C₂₂H₂₀F₃NO₄: C,63.0; H, 4.8; N, 3.3. Found C, 63.0; H, 4.8; N, 3.5.

Step C: Preparation of3,4-difluoro-2-[2-fluoro-4-(4-hydroxy-1-butynyl)anilino]-N-(2-hydroxyethoxy)benzamide

The title compound was prepared by reaction of3,4-difluoro-2-{2-fluoro-4-[4-(tetrahydro-2H-pyran-2-yloxy)-1-butynyl]anilino}benzoicacid with CDI and 2-(aminooxy)ethanol by the general procedure ofExample 1, Step E, then purified by column chromatography on silica gel(50% EtOAc/PE as eluant) to give3,4-difluoro-2-{2-fluoro-4-[4-(tetrahydro-2H-pyran-2-yloxy)-1-butynyl]anilino}-N-(2-hydroxyethoxy)benzamideas a viscous transparent oil which was immediately dissolved in EtOH andtreated with 1 M HCl according to the general procedure of Example 10,Step D. Purification of the resulting oil was carried out by filtrationthrough a plug of silica gel (EtOAc as eluant) to give3,4-difluoro-2-[2-fluoro-4-(4-hydroxy-1-butynyl)anilino]-N-(2-hydroxyethoxy)benzamideas a pale yellow crystalline solid (51%); m.p. (EtOAc/Et₂O) 126–129° C.¹H NMR [400 MHz, (CD₃)₂SO] δ 11.82 (br s, 1 H), 8.85 (br s, 1 H),7.45–7.39 (m, 1 H), 7.25–7.17 (m, 2H), 7.07 (dd, J=8.3, 1.4 Hz, 1 H),6.78 (dd, J=8.8, 8.8, 4.7 Hz, 1 H), 4.88 (t, J=5.6 Hz, 1 H), 4.73 (br s,1 H), 3.85 (t, J=4.8 Hz, 2 H), 3.59–3.53 (m, 4 H), 2.53 (t, J=6.9 Hz, 1H). Anal. calcd. for C₁₉H₁₇F₃N₂O₄.0.25Et₂O: C, 58.2; H, 4.8; N, 6.8.Found C, 58.1; H, 4.8; N, 7.1.

EXAMPLE 123,4-Difluoro-2-[2-fluoro-4-(3-hydroxy-3-methyl-1-butynyl)anilino]-N-(2-hydroxyethoxy)benzamide

3,4-difluoro-2-(2-fluoro-4-iodoanilino)-N-(2-hydroxyethoxy)benzamide,which can be prepared according to the procedure in PCT Publication No.WO 00/41505, and 2-methyl-3-butyn-2-ol were reacted in the presence ofCuI and (PhP₃)₂Cl₂ by the general procedure of Example 1, Step A, andthe mixture stirred at RT for 4 h. The reaction mixture was diluted with50% Et₂O/MeOH and filtered through Celite®. The filtrate wasconcentrated under reduced pressure and further purified by flashchromatography on silica (CH₂Cl_(2–10)% MeOH/CH₂Cl₂ gradient elution) togive3,4-difluoro-2-[2-fluoro-4-(3-hydroxy-3-methyl-1-butynyl)anilino]-N-(2-hydroxyethoxy)benzamide(97%) as a cream solid; m.p. (CH₂Cl₂/Hexane) 139–142° C. ¹H NMR [400MHz, (CD₃)₂SO] δ 11.80 (br s, 1 H), 8.78 (br s, 1 H), 7.46–7.40 (m, 1H), 7.28–7.19 (m, 2 H), 7.07 (dd, J=8.4, 1.5 Hz, 1 H), 6.79 (ddd, J=8.7,8.7, 4.7 Hz, 1 H), 5.43 (br s, 1 H), 4.70 (br s, 1 H), 3.86 (t, J=4.7Hz, 2 H), 3.57 (t, J=4.7 Hz, 2 H), 1.45 (s, 6 H). Anal. Calcd forC₂₀H₁₉F₃N₂O₄: C, 58.8; H, 4.7; N, 6.9. Found C, 58.5; H, 4.8; N, 6.7.

EXAMPLE 13

3,4-Difluoro-2-[2-fluoro-4-(3-hydroxy-3-methyl-1-pentynyl)anilino]-N-(2-hydroxyethoxy)benzamide

3,4-difluoro-2-(2-fluoro-4-iodoanilino)-N-(2-hydroxyethoxy)benzamidewhich can be prepared according to the procedure in PCT Publication No.WO 00/41505, and 3-methyl-1-pentyn-3-ol were reacted in the presence ofCuI and (PhP₃)₂PdCl₂ by the general procedure of Example 1, Step A, andthe mixture stirred at RT for 4 h. The reaction mixture was diluted with50% Et₂O/MeOH and filtered through Celite®. The filtrate wasconcentrated under reduced pressure and further purified by flashchromatography on silica (CH₂Cl₂-10% MeOH/CH₂Cl₂ gradient elution) togive3,4-difluoro-2-[2-fluoro-4-(3-hydroxy-3-methyl-1-pentynyl)anilino]-N-(2-hydroxyethoxy)benzamide(77%) as a white solid; m.p. (CH₂Cl₂/Hexane) 127–131° C.

¹H NMR [400 MHz, (CD₃)₂SO] δ 11.79 (br s, 1 H), 8.79 (br s, 1 H),7.45–7.39 (m, 1H), 7.28–7.18 (m, 2 H), 7.07 (dd, J=8.4, 1.5 Hz, 1 H),6.79 (ddd, J=8.7, 8.7, 4.6 Hz, 1 H), 5.31 (br s, 1 H), 4.71 (br s, 1 H),3.86 (t, J=4.7 Hz, 2 H), 3.57 (t, J=4.7 Hz, 2H), 1.68–1.57 (m, 2 H),1.40 (s, 3 H), 0.98 (t, J=7.4 Hz, 3 H). Anal. Calcd for C₂₁H₂₁F₃N₂O₄: C,59.7; H, 5.0; N, 6.6. Found C, 59.9; H, 5.1; N, 6.9.

EXAMPLE 14

2-[4-(3-Aminopropyl)-2-fluoroanilino]-3,4-difluoro-N-(2-hydroxyethoxy)benzamide

The product of Example 9,2-[4-(3-amino-1-propynyl)-2-fluoroanilino]-3,4-difluoro-N-(2-hydroxyethoxy)benzamidewas dissolved in absolute EtOH and hydrogenated in the presence of 5%Pd/C by the general procedure of Example 1, Step D. Purification of theresulting oil was carried out by column chromatography on silica gel (1%NH₄OH in 25% MeOH/CH₂Cl₂ as eluant) to give2-[4-(3-aminopropyl)-2-fluoroanilino]-3,4-difluoro-N-(2-hydroxyethoxy)benzamideas a cream solid (46%); m.p. (MeOH/CH₂Cl₂) 178–181° C. ¹H NMR [400 MHz,(CD₃)₂SO] δ 7.61–7.53 (m, 1 H), 6.97–6.87 (m, 2 H), 6.78 (dd, J=8.2, 1.3Hz, 1 H), 6.60 (dd, J=15.1, 8.6 Hz, 1 H), 4.10 (br s, 1 H), 3.77 (t,J=5.0 Hz, 2 H), 3.56 (t, J=5.0 Hz, 2 H), 2.70 (t, J=7.3 Hz, 2 H), 2.53(t, J=8.0 Hz, 2 H), 1.75 (pentet, J=7.5 Hz, 2 H). Not all exchangeableprotons observed. Anal. calcd. for C₁₈H₂₀F₃N₃O₃: C, 56.4; H, 5.3; N,11.0. Await Found.

EXAMPLE 15

2-{4-[3-(Dimethylamino)propyl]-2-fluoroanilino}-3,4-difluoro-N-(2-hydroxyethoxy)benzamide

Step A: Preparation of methyl3,4-difluoro-2-[2-fluoro-4-(3-hydroxy-1-propynyl)anilino]benzoate

The title compound was prepared by Sonogashira reaction of propargylalcohol and methyl 3,4-difluoro-2-(2-fluoro-4-iodoanilino)benzoate bythe general procedure of Example 1, Step A. The oil resulting fromworkup was purified by chromatography on silica gel (20% EtOAc/PE aseluant), to give methyl3,4-difluoro-2-[2-fluoro-4-(3-hydroxy-1-propynyl)anilino]benzoate as apale yellow solid (94%); m.p. (Et₂O/hexane) 116–120° C. ¹H NMR [400 MHz,(CD₃)₂SO] δ 8.79 (s, 1H), 7.79 (ddd, J=8.3, 5.9, 2.0 Hz, 1 H), 7.30 (dd,J=12.2, 1.8 Hz, 1 H), 7.26–7.17 (m, 1 H), 7.15 (dd, J=8.5, 1.6 Hz, 1 H),6.92 (ddd, J=8.8, 8.8, 4.7 Hz, 1 H), 5.31 (br s, 1 H), 4.28 (s, 2 H),3.81 (s, 3 H). Anal. calcd. for C₁₇H₁₂F₃NO₃: C, 60.9; H, 3.6; N, 4.2.Found C, 61.4; H, 3.9; N, 4.7.

Step B: Preparation of methyl3,4-difluoro-2-[2-fluoro-4-(3-hydroxypropyl)anilino]benzoate

Methyl 3,4-difluoro-2-[2-fluoro-4-(3-hydroxy-1-propynyl)anilino]benzoatewas dissolved in absolute EtOH and hydrogenated in the presence of 5%Pd/C by the general procedure of Example 1, Step D. Purification of theresulting oil was carried out by column chromatography on silica gel(20% EtOAc/PE as eluant) to give methyl3,4-difluoro-2-[2-fluoro-4-(3-hydroxypropyl)anilino]benzoate as a waxywhite solid (93%), used directly in the next step. ¹H NMR [400 MHz,(CD₃)₂SO] δ 8.81 (s, 1 H), 7.78 (ddd, J=9.0, 6.1, 2.0 Hz, 1 H),7.10–7.02 (m, 2 H), 6.98 (ddd, J=8.3, 8.3, 4.0 Hz, 1 H), 6.94 (dd,J=8.2, 1.9 Hz, 1 H), 4.46 (t, J=4.8 Hz, 1 H), 3.82 (s, 3 H), 3.43–3.37(m, 2 H), 2.58 (t, J=7.7 Hz, 2 H), 1.74–1.66 (m, 2 H). LCMS (APCI−) 338(M−H).

Step C: Preparation of3,4-difluoro-2-[2-fluoro-4-(3-hydroxypropyl)anilino]benzoic acid

Methyl 3,4-difluoro-2-[2-fluoro-4-(3-hydroxypropyl)anilino]benzoate wasdeprotected using EtOH/1 M NaOH as above to afford, after workup,3,4-difluoro-2-[2-fluoro-4-(3-hydroxypropyl)anilino]benzoic acid as awhite solid (99%); m.p. (EtOAc/hexane) 130–133° C. ¹H NMR [400 MHz,(CD₃)₂SO] δ 13.66 (br s, 1 H), 9.25 (br s, 1 H), 7.81 (ddd, J=8.5, 6.1,1.9 Hz, 1 H), 7.08 (dd, J=12.6, 1.7 Hz, 1 H), 7.05–6.96 (m, 2 H), 6.93(dd, J=8.2, 1.6 Hz, 1 H), 4.63 (br s, 1 H), 3.40 (t, J=6.3 Hz, 2 H),2.59 (t, J=7.7 Hz, 2 H), 1.74–1.65 (m, 2 H). Anal. calcd. forC₁₆H₁₄F₃NO₃: C, 59.1; H, 4.3; N, 4.3. Found C, 59.2; H, 4.4; N, 4.3.

Step D: Preparation of3,4-difluoro-2-[2-fluoro-4-(3-hydroxypropyl)anilino]-N-[2(vinyloxy)ethoxy]benzamide

The title compound was prepared from reaction of3,4-difluoro-2-[2-fluoro-4-(3-hydroxypropyl)anilino]benzoic acid with1-[2-(aminooxy)ethoxy]ethylene and DMT-MM by the general procedure ofExample 6, Step B, then purified by column chromatography on silica gel(20% EtOAc/PE as eluant) to give3,4-difluoro-2-[2-fluoro-4-(3-hydroxypropyl)anilino]-N-[2-(vinyloxy)ethoxy]benzamideas a white solid (46%), which was employed directly in the next step. ¹HNMR [400 MHz, (CD₃)₂SO] δ 11.93 (br s, 1 H), 8.79 (br s, 1 H), 7.44–7.38(m, 1 H), 7.14–7.05 (m, 1H), 7.04 (dd, J=12.6, 1.6 Hz, 1 H), 6.89 (dd,J=8.2, 1.6 Hz, 1 H), 6.82 (ddd, J=8.7, 8.7, 4.4 Hz, 1 H), 6.50 (dd,J=14.3, 6.7 Hz, 1 H), 4.45 (t, J=5.1 Hz, 1 H), 4.18 (dd, J=14.3, 1.9 Hz,1 H), 4.06–4.01 (m, 2 H), 3.98 (dd, J=6.6, 1.9 Hz, 1 H), 3.89–3.82 (m, 2H), 3.42–3.35 (m, 2 H), 2.56 (t, J=7.7 Hz, 2 H), 1.72–1.64 (m, 2 H).LCMS (APCI−) 409 (M−H).

Step E: Preparation of3,4-difluoro-2-[2-fluoro-4-(3-iodopropyl)anilino]-N-[2-(vinyloxy)ethoxy]benzamide

3,4-Difluoro-2-[2-fluoro-4-(3-hydroxypropyl)anilino]-N-[2-(vinyloxy)ethoxy]benzamide(710 mg, 1.73 mmol) was dissolved in THF (10 mL), to which was added TEA(875 mg, 8.65 mmol), followed by methanesulfonyl chloride (396 mg, 3.46mmol). This mixture was stirred at RT for 1 hour, then partitionedbetween water (100 mL) and EtOAc (100 mL). The EtOAc layer was washedwith water (100 mL), sat. NaHCO₃ (100 mL), brine (100 mL) and dried(Na₂SO₄). The solvent was removed under reduced pressure to give abright yellow oil (844 mg, 1.73 mmol) which was dissolved in EtOAc (15mL). NaI (5.19 g, 34.6 mmol) was added, and the mixture heated to 70° C.for 1.5 hours, at which time complete reaction was observed by TLC. Theexcess NaI was removed by filtration, and the EtOAc removed from thefiltrate under reduced pressure to afford a yellow oil which waspurified by chromatography on silica gel (10% EtOAc/PE as eluant).3,4-Difluoro-2-[2-fluoro-4-(3-iodopropyl)anilino]-N-[2-(vinyloxy)ethoxy]benzamidewas isolated as a pale yellow oil (474 mg, 53%). ¹H NMR [400 MHz,(CD₃)₂SO] δ 8.45 (s, 1 H), 7.50 (ddd, J=9.0, 5.8, 1.8 Hz, 1 H),7.26–7.17 (m, 1 H), 7.10 (dd, J=12.7, 1.7 Hz, 1 H), 6.96–6.86 (m, 2 H),6.38 (dd, J=14.3, 6.7 Hz, 1 H), 4.44–4.39 (m, 1 H), 4.15 (dd, J=14.3,1.9 Hz, 1 H), 3.97–3.91 (m, 2 H), 3.59 (br s, 2 H), 3.22 (t, J=6.7 Hz, 2H), 2.63 (t, J=7.4 Hz, 2 H), 2.05 (pentet, J=7.1 Hz, 2 H). Not allexchangeable protons were observed. HRMS (E+) calcd for C₂₀H₂₀F₃N₂O₃I520.0471 (M+), found 520.0467.

Step F: Preparation of2-{4-[3-(dimethylamino)propyl]-2-fluoroanilino}-3,4-difluoro-N-(2-hydroxyethoxy)benzamide

3,4-Difluoro-2-[2-fluoro-4-(3-iodopropyl)anilino]-N-[2-(vinyloxy)ethoxy]benzamide(200 mg, 0.39 mmol) was dissolved in DMA (10 mL), to which was addeddimethylamine (0.15 mL of a 40% solution in water). This mixture wasstirred at RT for 15 hours, then the DMA removed under reduced pressure,affording a yellow oil. This oil was then dissolved in EtOH (6 mL), towhich was added 1 M HCl solution (4 mL). The resulting mixture wasstirred at RT for 15 h. The reaction mixture was then diluted with water(50 mL) and this aqueous solution basicified with solid K₂CO₃ andsaturated with solid NaCl. The resulting solution was extracted withEtOAc (3×50 mL), the combined organic extract dried (Na₂SO₄) and thesolvent removed under reduced pressure to afford an oil. This oil waspurified by column chromatography on silica gel (1% NH₄OH in 25%MeOH/CH₂Cl₂ as eluant) to give2-{4-[3-(dimethylamino)propyl]-2-fluoroanilino}-3,4-difluoro-N-(2-hydroxyethoxy)benzamideas a cream foam (55 mg, 36%). ¹H NMR [400 MHz, (CD₃)₂SO] δ 11.70 (v brs, 1 H), 8.82 (br s, 1 H), 7.44–7.38 (m, 1 H), 7.14–7.06 (m, 1H), 7.05(dd, J=12.5, 1.6 Hz, 1 H), 6.89 (dd, J=8.2, 1.6 Hz, 1 H), 6.82 (ddd,J=8.7, 8.7, 4.5 Hz, 1 H), 4.53 (br s, 1 H), 3.85 (t, J=4.9 Hz, 2 H),3.57 (t, J=4.9 Hz, 2 H), 2.53 (t, J=7.5 Hz, 2 H), 2.24 (t, J=7.1 Hz, 2H), 2.16 (s, 6 H), 1.67 (q, J=7.5 Hz, 2H). Anal. calcd. forC₂₀H₂₄F₃N₃O₃.0.75H₂O: C, 56.5; H, 6.1; N, 9.9. Found C, 56.4; H, 6.4; N,9.1.

EXAMPLE 16

3,4-Difluoro-2-{2-fluoro-4-[3-(methylamino)propyl]anilino}-N-(2-hydroxyethoxy)benzamide

The product of Example 15, Step E,3,4-Difluoro-2-[2-fluoro-4-(3-iodopropyl)anilino]-N-[2-(vinyloxy)ethoxy]benzamidewas reacted with methylamine and then deprotected according to thegeneral procedure of Example 15, Step F, to afford3,4-difluoro-2-{2-fluoro-4-[3-(methylamino)propyl]anilino}-N-(2-hydroxyethoxy)benzamide as a pale brown solid (32%); m.p.(Et₂O) 112–116° C. ¹H NMR [400 MHz, (CD₃)₂SO] δ 9.61 (v br s, 1 H),7.57–7.50 (m, 1 H), 7.02–6.94 (m, 1H), 6.93 (dd, J=12.4, 1.5 Hz, 1 H),6.79 (dd, J=8.3, 1.5 Hz, 1 H), 6.65 (ddd, J=8.8, 8.8, 5.9 Hz, 1 H), 3.80(t, J=4.9 Hz, 2 H), 3.54 (t, J=4.9 Hz, 2 H), 2.66 (t, J=7.3 Hz, 2 H),2.52 (t, J=7.6 Hz, 2 H), 2.41 (s, 3 H), 1.73 (q, J=7.5 Hz, 2 H). Not allexchangeable protons were observed. Anal. calcd. forC₁₉H₂₂F₃N₃O₃.0.5H₂O: C, 56.2; H, 5.7; N, 10.3. Found C, 56.2; H, 5.6; N,10.2.

EXAMPLE 17

3,4-Difluoro-N-(2-hydroxyethoxy)-2-[[4-(hydroxymethyl)phenyl]amino]benzamide

Step A: Preparation of methyl4-[[2,3-difluoro-6-[[(2-hydroxyethoxy)amino]carbonyl]phenyl]amino]benzoate

2,3,4-Trifluorobenzoic acid and methyl 4-aminobenzoate were reacted inthe presence of LiHMDS solution in THF by the general procedure ofExample 1, Step B, to afford after workup, crude3,4-difluoro-2-[[4-(methoxycarbonyl)-phenyl]amino]benzoic acid as acream solid. This material was then coupled directly with2-(aminooxy)ethanol by the general procedure of Example 1; Step E, andpurified on flash silica (10% EtOAc as eluant) to give methyl4-[[2,3-difluoro-6-[[(2-hydroxyethoxy)amino]carbonyl]phenyl]amino]benzoate(48%) as a white solid; m.p. (EtOAc/hexanes) 158–160° C. ¹H NMR [400MHz, (CD₃)₂SO] δ 11.64 (br s, 1 H), 8.76 (br s, 1 H), 7.78 (d, J=8.8 Hz,2 H), 7.41–7.27 (m, 2 H), 6.80 (dd, J=8.8, 1.8 Hz, 2 H), 4.67 (br s, 1H), 3.78 (s, 3 H), 3.76 (t, J=4.8 Hz, 2 H), 3.50 (t, J=4.6 Hz, 2 H).Anal. Calcd for C₁₇H₁₆F₂N₂O₅: C, 55.7; H, 4.4; N, 7.7. Found: C, 55.7;H, 4.4; N, 7.6.

Step B: Preparation of4-[[2,3-difluoro-6-[[(2-hydroxyethoxy)amino]carbonyl]-phenyl]amino]benzoicacid

The product of Example 17, Step A, methyl4-[[2,3-difluoro-6-[[(2-hydroxyethoxy)amino]carbonyl]phenyl]amino]benzoate(306 mg, 0.84 mmol) was dissolved in ethanol (40 mL), to which was added1 M NaOH solution (40 mL). This mixture was stirred at room temperaturefor 15 hours, then poured into 1 M HCl solution (100 mL). The resultingprecipitate was extracted with EtOAc (3×80 mL) and the combined EtOAcextracts then combined and washed with water (2×100 mL) and saturatedNaCl (100 mL). The organic fraction was dried (Na₂SO₄), the solventremoved under reduced pressure and the resulting residue purified bycolumn chromatography on flash silica (50% EtOAc/hexanes as eluant) toafford4-[[2,3-difluoro-6-[[(2-hydroxyethoxy)amino]carbonyl]phenyl]-amino]benzoicacid as a crystalline white solid (168 mg, 57%); m.p. (EtOAc/hexanes)180–183° C.

¹H NMR [400 MHz, (CD₃)₂SO] δ 11.89 (br s, 2 H), 8.75 (br s, 1 H), 7.75(d, J=8.8 Hz, 2 H), 7.41–7.25 (m, 2 H), 6.79 (dd, J=8.6, 1.7 Hz, 2 H),4.76 (br s, 1 H), 3.76 (t, J=4.8 Hz, 2 H), 3.50 (t, J=4.8 Hz, 2 H).Anal. Calcd for C₁₆H₁₄F₂N₂O₅: C, 54.5; H, 4.0; N, 8.0. Found: C, 54.8;H, 3.9; N, 8.0.

Step C: Preparation of 2,3,4,5,6-pentafluorophenyl4-[[2,3-difluoro-6-[[(2-hydroxyethoxy)-amino]carbonyl]-phenyl]amino]benzoate

The product of Example 17, Step B,4-[[2,3-difluoro-6-[[(2-hydroxyethoxy)amino]carbonyl]phenyl]amino]benzoicacid (265 mg, 0.75 mmol), was dissolved in dry DMA (3 mL). The flask wassealed and flushed with nitrogen, then pyridine (65 mg, 0.83 mmol) andpentafluorophenyltrifluoroacetate (232 mg, 0.83 mmol) was added viasyringe. This reaction mixture was stirred at room temperature for 15hours, then all solvent was removed under reduced pressure. The residuewas partitioned between 1 M HCl (50 mL) and EtOAc (50 mL), then theEtOAc layer washed with water (50 mL), saturated NaCl (50 mL), dried(Na₂SO₄). The solvent was removed under reduced pressure to give an oilwhich was purified by column chromatography on flash silica (10%EtOAc/hexanes as eluant) to afford 2,3,4,5,6-pentafluorophenyl4-[[2,3-difluoro-6-[[(2-hydroxyethoxy)amino]carbonyl]phenyl]amino]benzoate(156 mg, 40%) as a white solid. ¹H NMR [400 MHz, (CD₃)₂SO] δ 11.65 (brs, 1 H), 9.01 (br s, 1 H), 7.96 (d, J=8.8 Hz, 2 H), 7.45–7.36 (m, 2 H),6.88 (dd, J=8.6, 1.3 Hz, 2 H), 4.67 (br s, 1 H), 3.81–3.72 (m, 2 H),3.54–3.46 (m, 2 H). HRMS (EI⁺) calcd for C₂₂H₁₃F₇N₂O₅ 518.0713 (M+),found 518.0702.

Step D: Preparation of 3,4-difluoro-N-(2-hydroxyethoxy)-2-[[4(hydroxymethyl)phenyl]amino]benzamide

The product of Example 17, Step C, 2,3,4,5,6-pentafluorophenyl4-[[2,3-difluoro-6-[[(2-hydroxyethoxy)amino]carbonyl]phenyl]amino]benzoate(150 mg, 0.29 mmol) was dissolved in THF (2 mL), then added dropwise toa solution of NaBH₄ (110 mg, 2.90 mmol) in water (2 mL). This mixturewas stirred at room temperature for 2 hours, acidified with 1 M HCl, anddiluted with water (50 mL). The resulting aqueous mixture was extractedwith EtOAc (2×50 mL), then the combined EtOAc fractions washed withwater (50 mL), saturated NaCl (50 mL), and dried (Na₂SO₄). The solventwas removed under reduced pressure and the resulting residue purified bycolumn chromatography on flash silica (50% EtOAc/hexanes as eluant) toafford3,4-difluoro-N-(2-hydroxyethoxy)-2-[[4-(hydroxymethyl)phenyl]amino]benzamideas a cream solid (36 mg, 37%); m.p. (EtOAc/hexanes) 73–77° C. ¹H NMR[400 MHz, (CD₃)₂SO] δ 11.73 (br s, 1 H), 8.68 (br s, 1 H), 7.41–7.35 (m,1H), 7.15 (d, J=8.5 Hz, 2 H), 7.14–7.06 (m, 1 H), 6.79 (dd, J=8.5, 2.3Hz, 2 H), 4.99 (t, J=5.7 Hz, 1 H), 4.72 (br s, 1 H), 4.38 (d, J=5.6, 2H), 3.80 (t, J=4.9 Hz, 2 H), 3.54 (t, J=4.9 Hz, 2 H). Anal. Calcd forC₁₆H₁₆F₂N₂O₄: C, 56.8; H, 4.8; N, 8.3. Found: C, 56.3; H, 4.7; N, 8.1.

EXAMPLE 18

3,4-Difluoro-2-[2-fluoro-4-(hydroxymethyl)anilino]-N-(2-hydroxyethoxy)benzamide

The product of Example4,3,4-Difluoro-2-(2-fluoro-4-vinylanilino)-N-(2-hydroxyethoxy)benzamide(170 mg, 0.48 mmol) was dissolved in MeOH (50 mL) and the solutioncooled to −78° C. (acetone/dry ice). Ozone was bubbled through thesolution until a pale blue-grey solution was obtained, then nitrogenbubbled through the solution until the blue colour disappeared. Asolution of NaBH₄ (92 mg, 2.41 mmol) in MeOH (10 mL) was added, thereaction mixture removed from the cold bath and allowed to stir for 0.5h. at RT. The MeOH was removed from the mixture under reduced pressureand the resulting residue partitioned between EtOAc (50 mL) and 1 M HCl(50 mL). The EtOAc layer was washed with water (50 mL) and brine (50mL), then dried (Na₂SO₄) and the solvent removed under reduced pressureto afford an oil which was purified by chromatography on silica gel (10%EtOAc as eluant).3,4-Difluoro-2-[2-fluoro-4-(hydroxymethyl)anilino]-N-(2-hydroxyethoxy)benzamidewas isolated as a pale yellow crystalline solid (99 mg, 58%); m.p.(Et₂O/hexane) 108–110° C. ¹H NMR [400 MHz, (CD₃)₂SO] δ 11.86 (br s, 1H), 8.74 (br s, 1 H), 7.44–7.37 (m, 1 H), 7.16–7.08 (m, 2 H), 7.02–6.97(m, 1 H), 6.86 (ddd, J=8.6, 8.6, 4.5 Hz, 1 H), 5.18 (t, J=5.7 Hz, 1 H),4.71 (br s, 1 H), 4.43 (d, J=5.8 Hz, 2 H), 3.85 (t, J=4.7 Hz, 2 H),3.60–3.52 (m, 2 H). Anal. calcd. for C₁₆H₁₅F₃N₂O₄: C, 53.9; H, 4.2; N,7.9. Found C, 54.2; H, 4.6; N, 7.6.

EXAMPLE 19

3,4-Difluoro-2-[2-fluoro-4-(2-hydroxyethyl)anilino]-N-(2-hydroxyethoxy)benzamide

Step A: Preparation of methyl3,4-difluoro-2-[2-fluoro-4-(2-hydroxyethyl)anilino]benzoate

Crude methyl 2-(4-allyl-2-fluoroanilino)-3,4-difluorobenzoate, preparedas above, was subjected to ozonolysis and reduction with NaBH₄ as aboveto afford methyl3,4-difluoro-2-[2-fluoro-4-(2-hydroxyethyl)anilino]benzoate as a paleyellow oil (37%). ¹H NMR [400 MHz, (CD₃)₂SO] δ 8.82 (br s, 1 H), 7.78(ddd, J=8.3, 6.1, 2.0 Hz, 1 H), 7.13–6.92 (m, 4 H), 4.64 (t, J=5.2 Hz, 1H), 3.83 (s, 3 H), 3.60 (q, J=6.3 Hz, 2 H), 2.69 (t, J=6.9 Hz, 2 H).LCMS (APCI+) 326 (M+H).

Step B: Preparation of3,4-difluoro-2-[2-fluoro-4-(2-hydroxyethyl)anilino]benzoic acid

Methyl 3,4-difluoro-2-[2-fluoro-4-(2-hydroxyethyl)anilino]benzoate wasdeprotected using EtOH/1 M NaOH as above to afford3,4-difluoro-2-[2-fluoro-4-(2-hydroxyethyl)anilino]benzoic acid as acrystalline cream solid (93%); m.p. (EtOAc/hexane) 196–200° C. ¹H NMR[400 MHz, (CD₃)₂SO] δ 13.67 (v br s, 1 H), 9.28 (br s, 1 H), 7.80 (ddd,J=8.4, 6.1, 1.8 Hz, 1 H), 7.13–6.93 (m, 4 H), 4.65 (br s, 1H), 3.63–3.55(br m, 2 H), 2.69 (t, J=6.8 Hz, 2 H). Anal. calcd. for C₁₅H₁₂F₃NO₃: C,57.9; H, 3.9; N, 4.5. Found C, 58.3; H, 4.1; N, 4.7.

Step C: Preparation of3,4-difluoro-2-[2-fluoro-4-(2-hydroxyethyl)anilino]-N-(2-hydroxyethoxy)benzamide

3,4-Difluoro-2-[2-fluoro-4-(2-hydroxyethyl)anilino]benzoic acid wasdissolved in MeOH and prepared from reaction with 2(aminooxy)ethanol andDMT-MM by the general procedure of Example 6, Step B, affording a crudeyellow oil after workup which was purified by filtration through a plugof silica gel (100% EtOAc as eluant).3,4-Difluoro-2-[2-fluoro-4-(2-hydroxyethyl)anilino]-N-(2-hydroxyethoxy)benzamidewas isolated as a viscous, transparent oil (57%). ¹H NMR [400 MHz,(CD₃)₂SO] δ 11.85 (v br s, 1 H), 8.77 (br s, 1 H), 7.44–7.37 (m, 1 H),7.15–7.05 (m, 1 H), 7.06 (dd, J=12.5, 1.7 Hz, 1 H), 6.90 (dd, J=8.2, 1.7Hz, 1 H), 6.81 (ddd, J=8.8, 8.8, 4.5 Hz, 1 H), 4.75 (br s, 1 H), 4.63(t, J=5.2 Hz, 1H), 3.86 (t, J=5.0 Hz, 2 H), 3.61–3.52 (m, 4 H), 2.66 (t,J=6.9 Hz, 2 H). HRMS (EI⁺) calcd. for C₂₀H₁₆F₂N₂O₃ 370.1129 (M⁺), found370.1133.

EXAMPLE 20

3,4-Difluoro-2-[2-fluoro-4-(3-hydroxypropyl)anilino]-N-(2-hydroxyethoxy)benzamide

The product of Example 10, Step D,3,4-Difluoro-2-[2-fluoro-4-(3-hydroxy-1-propynyl)anilino]-N-(2-hydroxyethoxy)-benzamidewas hydrogenated in absolute EtOH in the presence of 5% Pd/C by theprocedure of Example 1, Step D. An off-white solid was isolated whichwas purified by filtration through a plug of silica gel (EtOAc aseluant).3,4-Difluoro-2-[2-fluoro-4-(3-hydroxypropyl)anilino]-N-(2-hydroxyethoxy)benzamidewas isolated as a crystalline cream solid (52 mg, 73%); m.p.(EtOAc/Et₂O) 115–116° C. ¹H NMR [400 MHz, (CD₃)₂SO] δ 11.85 (br s, 1 H),8.83 (br s, 1 H), 7.44–7.37 (m, 1 H), 7.13–7.05 (m, 1 H), 7.03 (dd,J=12.6, 1.6 Hz, 1H), 6.88 (dd, J=8.2, 1.6 Hz, 1 H), 6.81 (ddd, J=8.7,8.7, 4.5 Hz, 1 H), 4.76 (br s, 1H), 4.46 (t, J=5.1 Hz, 1 H), 3.86 (t,J=4.8 Hz, 2 H), 3.57 (t, J=5.0 Hz, 2 H), 3.43–3.35 (m, 2 H), 2.58–2.52(m, 2 H), 1.72–1.64 (m, 2 H). Anal. calcd. for C₁₈H₁₉F₃N₂O₄.0.5Et₂O: C,57.0; H, 5.7; N, 6.7. Found C, 56.6; H, 5.5; N, 6.8.

EXAMPLE 21

3,4-Difluoro-2-[2-fluoro-4-(4-hydroxybutyl)anilino]-N-(2-hydroxyethoxy)benzamide

The product of Example 11,3,4-Difluoro-2-[2-fluoro-4-(4-hydroxy-1-butynyl)anilino]-N-(2-hydroxyethoxy)-benzamidewas hydrogenated in absolute EtOH in the presence of 5% Pd/C by theprocedure of Example 1, Step D. Purification of the resulting oil wascarried out by filtration through a plug of silica gel (EtOAc as eluant)to afford3,4-difluoro-2-[2-fluoro-4-(4-hydroxybutyl)anilino]-N-(2-hydroxyethoxy)benzamideas a white crystalline solid (46%); m.p. (Et₂O/EtOAc) 65-69° C. ¹H NMR[400 MHz, (CD₃)₂SO] δ 11.90 (br s, 1 H), 8.83 (br s, 1 H), 7.44–7.38 (m,1 H), 7.13–7.07 (m, 1 H), 7.03 (dd, J=12.5, 1.6 Hz, 1 H), 6.88 (dd,J=8.2, 1.7 Hz, 1 H), 6.82 (ddd, J=8.7, 8.7, 4.3 Hz, 1 H), 4.76 (v br s,1 H), 4.35 (t, J=5.2 Hz, 1H), 3.84 (t, J=4.8 Hz, 2 H), 3.56 (t, J=4.9Hz, 2 H), 3.43–3.34 (m, 2 H), 2.55–2.47 (m, 2 H), 1.61–1.51 (m, 2 H),1.46–1.37 (m, 2 H). Anal. calcd. for C₁₉H₂₁F₃N₂O₄: C, 57.3; H, 5.3; N,7.0. Found C, 57.4; H, 5.4; N, 6.9.

EXAMPLE 22

2-[4-(2,3-Dihydroxypropyl)-2-fluoroanilino]-3,4-difluoro-N-(2-hydroxyethoxy)benzamide

The product of Example6,2-(4-allyl-2-fluoroanilino)-3,4-difluoro-N-(2-hydroxyethoxy)benzamide(227 mg, 0.62 mmol) was dissolved in tert-butanol (15 mL) and water (15mL) to which was added K₂CO₃ (257 mg, 1.86 mmol), K₃Fe(CN)₆ (613 mg,1.86 mmol) and 1,4-diazabicyclo[2.2.2]octane (70 mg, 0.62 mmol). To thismixture was then added a 4% w/w solution of OsO₄ in water (0.21 ml,0.031 mmol). The reaction was then stirred 15 h. at room temperature,poured into 10% Na₂S₂O₄ (100 mL), and this aqueous solution extractedwith EtOAc (3×80 mL). The EtOAc extracts were combined, washed withsaturated NaCl solution and dried (Na₂SO₄), then the solvent removedunder reduced pressure to afford a viscous oil. This oil was purified byflash chromatography on silica (10% MeOH/CH₂Cl₂ as eluant) to give2-[4-(2,3-dihydroxypropyl)-2-fluoroanilino]-3,4-difluoro-N-(2-hydroxyethoxy)benzamideas a cream solid (159 mg, 64%); m.p. (Et₂O) 118–120° C. ¹H NMR [400 MHz,(CD₃)₂SO] δ 11.86 (br s, 1 H), 8.78 (br s, 1 H), 7.44–7.37 (m, 1H),7.14–7.08 (m, 1 H), 7.05 (dd, J=12.8, 1.7 Hz, 1 H), 6.90 (dd, J=8.2, 1.6Hz, 1H), 6.81 (ddd, J=8.8, 8.8, 4.5 Hz, 1 H), 4.71 (br s, 1 H), 4.55 (t,J=6.1 Hz, 2 H), 3.57 (t, J=4.9 Hz, 2 H), 3.63–3.55 (m, 2 H), 3.30–3.20(m, 2 H), 2.71 (dd, J=13.8, 4.5 Hz, 1 H), 2.43–2.49 (m, 2 H). HRMS (EI⁺)calcd. For C₁₈H₁₉F₃N₂O₅ 400.1246 (M+), found 400.1248. Anal. calcd. forC₁₈H₁₉F₃N₂O₅: C, 54.0; H, 4.8; N, 7.0. Found: C, 54.0; H, 4.8; N, 7.0.

EXAMPLE 23

3,4-Difluoro-2-[2-fluoro-4-(3-hydroxy-3-methylbutyl)anilino]-N-(2-hydroxyethoxy)benzamide

The product of Example 12,3,4-difluoro-2-[2-fluoro-4-(3-hydroxy-3-methyl-1-butynyl)anilino]-N-(2-hydroxyethoxy)benzamidewas hydrogenated in absolute ethanol in the presence of 5% Pd/C by thegeneral procedure of Example 1, Step D. The resulting crude solid waspurified by filtration through a plug of silica (MeOH as eluant) to give3,4-difluoro-2-[2-fluoro-4-(3-hydroxy-3-methylbutyl)anilino]-N-(2-hydroxyethoxy)benzamide(99%) as a cream foam (hygroscopic). ¹H NMR [400 MHz, (CD₃)₂SO] δ 10.09(br s, 1 H), 7.60–7.55 (m, 1 H), 7.03–6.91 (m, 2 H), 6.86 (dd, J=8.2,1.4 Hz, 1 H), 6.71 (ddd, J=8.6, 8.6, 5.8 Hz, 1 H), 4.22 (br s, 1 H),3.79 (t, J=4.9 Hz, 2 H), 3.55 (t, J=4.9 Hz, 2 H), 2.60–2.49 (m, 2 H),1.65–1.59 (m, 2 H), 1.13 (s, 6 H). HRMS (EI⁺) calcd for C₂₀H₂₃F₃N₂O₄412.1610 (M+), found 412.1617.

EXAMPLE 24

3,4-Difluoro-2-[2-fluoro-4-(3-hydroxy-3-methylpentyl)anilino]-N-(2-hydroxyethoxy)benzamide

The product of Example 13,3,4-difluoro-2-[2-fluoro-4-(3-hydroxy-3-methyl-1-pentynyl)anilino]-N-(2-hydroxyethoxy)benzamidewas hydrogenated in absolute ethanol in the presence of 5% Pd/C by thegeneral procedure of Example 1, Step D. The resulting crude solid waspurified by filtration through a plug of silica (MeOH as eluant) to give3,4-difluoro-2-[2-fluoro-4-(3-hydroxy-3-methylpentyl)anilino]-N-(2-hydroxyethoxy)benzamide(98%) as a light yellow foam (hygroscopic). ¹H NMR [400 MHz, (CD₃)₂SO] δ9.62 (br s, 1 H), 7.54–7.48 (m, 1 H), 7.04–6.96 (m, 2 H), 6.86 (dd,J=8.2, 1.6 Hz, 1 H), 6.75 (ddd, J=8.6, 5.2 Hz, 1 H), 4.08 (br s, 1 H),3.80 (t, J=4.9 Hz, 2 H), 3.53 (t, J=4.9 Hz, 2 H), 2.55–2.50 (m, 2 H),1.60–1.54 (m, 2 H), 1.41 (q, I=7.6 Hz, 2 H), 1.06 (s, 3 H), 0.84 (t,J=7.6 Hz, 3 H). HRMS (EI⁺) calcd for C₂₁H₂₅F₃N₂O₄ 426.1766 (M⁺), found426.1770.

EXAMPLE 25

3,4-Difluoro-2-[[2-fluoro-4-(3-methoxypropyl)phenyl]amino]-N-(2-hydroxyethoxy)benzamide

Step A: Preparation of 2-fluoro-4-(3-methoxy-1-propynyl)aniline

2-Fluoro-4-iodoaniline and methyl propargyl ether were combined by thegeneral procedure of Example 1, Step A, to prepare2-fluoro-4-(3-methoxy-1-propynyl)aniline. The desired product wasisolated as a dark orange solid (91%);

¹H NMR [400 MHz, (CD₃)₂SO] δ 7.07 (dd, J=12.2, 1.8 Hz, 1 H), 6.98 (dd,J=8.2, 1.7 Hz, 1 H), 6.71 (dd, J=9.3, 8.4 Hz, 1 H), 5.56 (s, 2 H), 4.26(s, 2 H), 3.29 (s, 3 H).

Step B: Preparation of3,4-difluoro-2-[[2-fluoro-4-(3-methoxy-1-propynyl)phenyl]amino]benzoicacid

2,3,4-Trifluorobenzoic acid and the product of Example 25, Step A,2-fluoro-4-(3-methoxy-1-propynyl)aniline, were reacted in the presenceof LiHMDS solution in THF by the general procedure of Example 1, Step B.After workup, followed by purification by chromatography on silica gel(10% EtOAc/hexanes as eluant),3,4-difluoro-2-[[2-fluoro-4-(3-methoxy-1-propynyl)phenyl]amino]-benzoicacid was isolated (62%) as a pale yellow solid; m.p. (EtOAc/hexanes)221–223° C. ¹H NMR [400 MHz, (CD₃)₂SO] δ 13.60 (br s, 1 H), 9.27 (br s,1 H), 7.85–7.79 (m, 1H,), 7.36 (dd, J=12.0, 1.8 Hz, 1 H), 7.20 (dd,J=8.3, 1.5 Hz, 1 H), 7.18–7.11 (m, 1 H), 6.96 (td, 8.8, 5.5 Hz, 1 H),4.31 (s, 2 H), 3.32 (s, 3 H). Anal. Calcd for C₁₇H₁₂F₃NO₃: C, 60.9; H,3.6; N, 4.2. Found: C, 61.4; H, 3.6; N, 4.2.

Step C: Preparation of3,4-difluoro-2-[[2-fluoro-4-(3-methoxypropyl)phenyl]-amino]benzoic acid

The product of Example 25, Step B,3,4-difluoro-2-[[2-fluoro-4-(3-methoxy-1-propynyl)phenyl]amino]benzoicacid, was hydrogenated in absolute ethanol in the presence of 5% Pd/C asabove in Example 1, Step D. The resulting crude solid was purified byfiltration through a plug of silica gel (50% EtOAc/hexanes as eluant) togive 3,4-difluoro-2-[[2-fluoro-4-(3-methoxypropyl)phenyl]amino]benzoicacid as a white solid (65%); m.p. (Et₂O/hexanes) 125–127° C. ¹H NMR [400MHz, (CD₃)₂SO] δ 13.35 (br s, 1 H), 9.27 (br s, 1 H), 7.82 (ddd, J=8.3,6.1, 1.9 Hz, 1 H), 7.08 (dd, J=12.4, 1.7 Hz, 1 H), 7.05–6.96 (m, 2 H),6.93 (dd, J=8.2, 1.8 Hz, 1 H), 3.33 (t, J=6.4 Hz, 2 H), 3.23 (s, 3 H),2.59 (t, J=7.7 Hz, 2 H), 1.83–1.73 (m, 2 H). Anal. Calcd forC₁₇H₁₆F₃NO₃: C, 60.2; H, 4.8; N, 4.1. Found: C, 60.2; H, 4.7; N, 4.1.

Step D: Preparation of3,4-difluoro-2-[[2-fluoro-4-(3-methoxypropyl)phenyl]-amino]-N-(2-hydroxyethoxy)benzamide

The title compound was prepared from reaction of the product of Example25, Step C,3,4-difluoro-2-[[2-fluoro-4-(3-methoxypropyl)phenyl]amino]benzoic acidwith CDI and 2-(aminooxy)ethanol, by the general procedure of Example 1,Step E, then purified by flash column chromatography on silica gel (50%EtOAc/hexanes) to give3,4-difluoro-2-[[2-fluoro-4-(3-methoxypropyl)phenyl]-amino]-N-(2-hydroxyethoxy)benzamideas a cream solid (69%); m.p. (Et₂O/hexanes) 136–137° C. ¹H NMR [400 MHz,(CD₃)₂SO] δ 11.85 (br s, 1 H), 8.77 (br s, 1 H), 7.43–7.36 (m, 1 H),7.15–7.00 (m, 2 H), 6.95–6.77 (m, 2 H), 4.71 (br s, 1 H), 3.85 (t,J=4.8, 2 H), 3.56 (t, J=4.8, 2 H), 3.33 (t, J=6.4 Hz, 2 H), 3.23 (s, 3H), 2.56 (t, J=7.7 Hz, 2 H), 1.80–1.71 (m, 2 H).

EXAMPLE 26

3,4-Difluoro-2-[[2-fluoro-4-(methylthio)phenyl]amino]-N-(2-hydroxyethoxy)benzamide

Step A: Preparation of 4-amino-3-fluorophenyl Thiocyanate

A solution of bromine (3.02 g, 18.9 mmol) in sodium bromide-saturatedmethanol (11 mL) was added dropwise to a solution of 2-fluoroaniline(2.00 g, 18.0 mmol) and potassium thiocyanate (5.25 g, 54.0 mmol) inmethanol (45 mL). The mixture was stirred for 0.5 hours, at roomtemperature, poured into water (300 mL) and made basic with solidNa₂CO₃. This aqueous mixture was extracted with Et₂O (5×30 mL), then thecombined Et₂O extracts were washed with water (2×100 mL), saturated NaCl(100 mL), and dried (Na₂SO₄). Removal of the solvent under reducedpressure afforded a pale yellow liquid which was purified by dry flashcolumn chromatography on silica (2.5% Et₂O/hexanes as eluant) to give4-amino-3-fluorophenyl thiocyanate as a white solid (1.60 g, 53%); m.p.36–38° C. ¹H NMR (400 MHz, CDCl₃) δ 7.25 (dd, J=10.5, 2.2 Hz, 1 H), 7.18(ddd, J=8.3, 2.2, 1.0 Hz, 1 H), 6.78 (dd, J=9.0, 8.3 Hz), 4.03 (br s,2H). Anal. Calcd for C₇H₅FN₂S: C, 50.0; H, 3.0; N, 16.7. Found: C, 50.2;H, 3.0; N, 16.7.

Step B: Preparation of 2-fluoro-4-methylthioaniline

A solution of the product of Example 26, Step A, 4-amino-3-fluorophenylthiocyanate (500 mg, 2.97 mmol), in ethanol (7.5 mL) was added to asolution of sodium sulfide monohydrate (714 mg, 2.97 mmol) in water (1.5mL) and the mixture heated at 50° C. for 2 hours. Methyl iodide (464 mg,3.27 mmol) in ethanol (0.5 mL) was added and heating continued for afurther 4 hours. The reaction mixture was then diluted with water (15mL) and extracted with Et₂O (4×5 mL). The combined Et₂O extracts werewashed with water (3×10 mL), saturated NaCl (10 mL), and dried (Na₂SO₄),followed by removal of the solvent under reduced pressure to afford apale yellow oil. This material was purified by dry flash columnchromatography on silica (5% Et₂O/hexanes as eluant) to give2-fluoro-4-methylthioaniline as a pale yellow oil (407 mg, 87%); ¹H NMR(400 MHz, CDCl₃) δ 7.01 (dd, J=11.3, 2.1 Hz, 1 H), 6.94 (ddd, J=8.2,2.1, 0.9 Hz, 1 H), 6.71 (dd, J=9.3, 8.2 Hz, 1 H), 3.67 (br s, 2 H), 2.42(s, 3 H).

Step C: Preparation of3,4-difluoro-2-[[2-fluoro-4-(methylthio)phenyl]amino]-benzoic acid

2,3,4-Trifluorobenzoic acid and the product of Example 26, Step B,2-fluoro-4-methylthioaniline, were reacted in the presence of LiHMDSsolution in THF by the general procedure of Example 1, Step B. Afterworkup, this material was purified by dry flash column chromatography onsilica (0.5% Et₂O in 1:1 CH₂Cl₂/hexanes as eluant) to afford3,4-difluoro-2-[[2-fluoro-4-(methylthio)phenyl]amino]benzoic acid as acream solid (52%); m.p. (Et₂O/hexanes) 210–220° C. ¹H NMR (400 MHz,CDCl₃) δ 13.70 (br s, 1 H), 9.24 (br s, 1 H), 7.81 (ddd, J=9.0, 6.1, 2.1Hz, 1 H), 7.20 (dd, J=11.8, 1.9 Hz, 1 H), 7.03–6.99 (m, 3 H), 2.47 (s, 3H). Anal. Calcd for C₁₄H₁₀F₃NO₂S.0.125 Et₂O: C, 54.0; H, 3.5; N, 4.3.Found: C, 54.2; H, 3.3; N, 4.5.

Step D: Preparation of3,4-difluoro-2-[[2-fluoro-4-(methylthio)phenyl]amino]-N-(2-hydroxyethoxy)benzamide

The title compound was prepared from reaction of the product of Example26, Step C, 3,4-difluoro-2-[[2-fluoro-4-(methylthio)phenyl]amino]benzoicacid, with CDI and 2-(aminooxy)ethanol by the general procedure ofExample 1, Step E. Then, after workup, the crude solid triturated withEt₂O and washed with pentane to afford3,4-difluoro-2-[[2-fluoro-4-(methylthio)phenyl]amino]-N-(2-hydroxyethoxy)benzamideas a white solid (80%); m.p. (Et₂O) 108–111° C. ¹H NMR [400 MHz,(CD₃)₂SO] δ 11.80 (br s, 1 H), 8.77 (br s, 1 H), 7.40 (ddd, J=9.0, 5.8,2.0 Hz, 1 H), 7.18 (dd, J=12.0, 2.2 Hz, 1 H), 7.13 (ddd, J=9.9, 9.0, 7.2Hz, 1 H), 6.99 (ddd, J=8.5, 2.4, 0.8 Hz, 1 H), 6.87 (td, J=8.9, 4.5 Hz,1 H), 4.71 (br s, 1 H), 3.86 (t, J=4.9 Hz, 2 H), 3.57 (t, J=4.9 Hz, 2H), 2.45 (s, 3 H). Anal. Calcd for C₁₆H₁₅F₃N₂O₃S: C, 51.6; H, 4.1; N,7.5. Found: C, 52.1; H, 4.3; N, 7.6.

EXAMPLE 27

3,4-Difluoro-2-[[2-fluoro-4-(ethylthio)phenyl]amino]-N-(2-hydroxyethoxy)benzamide

Step A: Preparation of 2-fluoro-4-ethylthioaniline

A solution of the product of Example 26, Step A, 4-amino-3-fluorophenylthiocyanate (500 mg, 2.97 mmol), in ethanol (7 mL) was added dropwise toa solution of Na₂S.9H₂O (714 mg, 2.97 mmol) in water (1.5 mL) and theresulting mixture stirred at 50° C. for 1 hour. A solution of ethyliodide (510 mg, 3.27 mmol) in ethanol (1 mL) was then added and thereaction stirred at 50° C. for a further 6 hours. The mixture wasdiluted with water (30 mL) and extracted with Et₂O (4×10 mL), then thecombined Et₂O extracts washed with water (3×20 mL), saturated NaCl (20mL) and dried (Na₂SO₄). Removal of the solvent under reduced pressureafforded a pale yellow oil which was purified by dry flash columnchromatography on silica (5% Et₂O/hexanes as eluant) to afford2-fluoro-4-ethylthioaniline as a colourless oil (470 mg, 92%). ¹H NMR(400 MHz, CDCl₃) δ 7.08 (dd, J=11.3, 2.0 Hz, 1 H), 7.01 (ddd, J=8.2,2.0, 0.9 Hz, 1 H), 6.71 (dd, J=9.3, 8.2 Hz, 1 H), 3.81 (br s, 2 H), 2.80(q, J=7.3 Hz, 2 H), 1.24 (t, J=7.3 Hz, 3 H).

Step B: Preparation of3,4-difluoro-2-[[2-fluoro-4-(ethylthio)phenyl]amino]-benzoic acid

2,3,4-Trifluorobenzoic acid and the product of Example 27, Step A,2-fluoro-4-ethylthioaniline, were reacted in the presence of LiHMDSsolution in THF by the general procedure of Example 1, Step B. Afterworkup, a yellow solid was obtained which was purified by dry flashcolumn chromatography on silica (0.5% Et₂O in 1:1 CH₂Cl₂/hexanes aseluant) to afford3,4-difluoro-2-[[2-fluoro-4-(ethylthio)phenyl]amino]benzoic acid as ayellow solid (55%); m.p. (Et₂O) 136–139° C. ¹H NMR (400 MHz, CDCl₃) δ13.70 (br s, 1 H), 9.24 (br s, 1 H), 7.81 (ddd, J=9.2, 6.1, 2.1 Hz, 1H), 7.26 (dd, J=11.8, 2.0 Hz, 1 H), 7.08 (dd, J=8.3, 2.0 Hz, 1 H), 7.06(td, J=9.7, 7.0 Hz, 1 H), 7.02 (ddd, J=9.2, 8.3, 4.7 Hz, 1 H), 2.96 (q,J=7.3 Hz, 2 H), 1.22 (t, J=7.3 Hz, 3 H). Anal. Calcd for C₁₅H₁₂F₃NO₂S:C, 55.0; H, 3.7; N, 4.3. Found: C, 55.5; H, 3.7; N, 4.3.

Step C: Preparation of3,4-difluoro-2-[[2-fluoro-4-(ethylthio)phenyl]amino]-N-(2-hydroxyethoxy)benzamide

The title compound was prepared from reaction of the product of Example27, Step B, 3,4-difluoro-2-[[2-fluoro-4-(ethylthio)phenyl]amino]benzoicacid with CDI and 2-(aminooxy)ethanol by the general procedure ofExample 1, Step E. Then, after workup, the crude solid triturated withEt₂O and washed with pentane to afford3,4-difluoro-2-[[2-fluoro-4-(ethylthio)phenyl]amino]-N-(2-hydroxyethoxy)benzamideas a white solid (65%); m.p. (Et₂O) 129–132° C. ¹H NMR [400 MHz,(CD₃)₂SO] δ 11.80 (br s, 1 H), 8.77 (br s, 1 H), 7.41 (ddd, J=9.0, 5.8,2.1 Hz, 1 H), 7.23 (dd, J=11.8, 2.1 Hz, 1 H), 7.15 (ddd, J=9.9, 8.9, 7.2Hz, 1 H), 7.04 (ddd, J=8.5, 2.1, 0.9 Hz, 1 H), 6.85 (ddd, J=9.9, 8.5,4.2 Hz, 1 H), 4.72 (br s, 1 H), 3.85 (t, J=4.9 Hz, 2 H), 3.57 (t, J=4.9Hz, 1 H), 2.92 (q, J=7.3 Hz, 2 H), 1.20 (t, J=7.3 Hz, 3 H). Anal. Calcdfor C₁₇H₁₇F₃N₂O₃S: C, 52.8; H, 4.4; N, 7.3. Found: C, 53.0; H, 4.7; N,7.2.

EXAMPLE 28

3,4-Difluoro-2-[[2-fluoro-4-(methylsulfonyl)phenyl]amino]-N-(2-hydroxyethoxy)benzamide

Step A: Preparation of3,4-difluoro-2-[[2-fluoro-4-(methylsulfonyl)phenyl]-amino]benzoic acid

CH₂Cl₂ (2 mL) was added to a mixture of the product of Example 26, StepC, 3,4-difluoro-2-[[2-fluoro-4-(methylthio)phenyl]amino]benzoic acid(150 mg, 0.48 mmol), and m-chloroperbenzoic acid (295 mg, 1.20 mmol).The reaction was stirred at room temperature for 4 hours, thenconcentrated, and the crude reaction mixture loaded directly onto acolumn for purification by dry flash chromatography on silica (9%Et₂O/CH₂Cl₂ as eluant).3,4-Difluoro-2-[[2-fluoro-4-(methylsulfonyl)phenyl]amino]benzoic acidwas isolated as a white solid (141 mg, 85%); m.p. (Et₂O) 220–224° C. ¹HNMR [400 MHz, (CD₃)₂SO] δ 13.60 (br s, 1 H), 9.27 (br s, 1 H), 7.84(ddd, J=8.7, 5.9, 1.9 Hz, 1 H), 7.76 (dd, J=11.0, 2.1 Hz, 1 H), 7.60(ddd, J=8.5, 2.1, 0.6 Hz, 1 H), 7.31 (td, J=9.3, 7.4 Hz, 1 H), 7.05 (td,J=8.5, 5.4 Hz, 1 H), 3.20 (s, 3 H). Anal. Calcd for C₁₄H₁₀F₃NO₄S: C,46.3; H, 3.3; N, 3.9. Found: C, 46.7; H, 3.0; N, 3.8.

Step) B: Preparation of3,4-difluoro-2-[[2-fluoro-4-(methylsulfonyl)phenyl]-amino]-N-(2-hydroxyethoxy)benzamide

The title compound was prepared from reaction of the product of Example28, Step A,3,4-difluoro-2-[[2-fluoro-4-(methylsulfonyl)phenyl]amino]benzoic acid,with CDI and 2-(aminooxy)ethanol by the general procedure of Example 1,Step E. Then, after workup, the crude solid purified by dry flash columnchromatography on silica (5% isopropanol/hexanes as eluant) to afford3,4-difluoro-2-[[2-fluoro-4-(methylsulfonyl)phenyl]amino]-N-(2-hydroxyethoxy)benzamideas a white solid (52%); m.p. (Et₂O) 85–88° C. ¹H NMR [400 MHz, (CD₃)₂SO]δ 11.78 (br s, 1 H), 8.88 (br s, 1 H), 7.72 (dd, J=11.1, 2.1 Hz, 1 H),7.55 (ddd, J=8.8, 2.1, 0.6 Hz, 1 H), 7.48–7.35 (m, 2 H), 6.87 (td,J=8.8, 4.0 Hz, 1 H), 4.68 (br s, 1 H), 3.81 (t, J=4.6 Hz, 2 H), 3.54(td, J=4.9, 4.2 Hz, 2 H), 3.18 (s, 3 H). Anal. Calcd for C₁₆H₁₅F₃N₂O₅S:C, 47.5; H, 3.6; N, 6.9. Found: C, 47.3; H, 3.8; N, 6.6.

EXAMPLE 29

3,4-Difluoro-2-(2-fluoro-4-propylanilino)-N-(2-hydroxyethoxy)benzamide

The product of Example6,2-(4-Allyl-2-fluoroanilino)-3,4-difluoro-N-(2-hydroxyethoxy)benzamidewas dissolved in absolute EtOH and hydrogenated in the presence of 5%Pd/C by the procedure of Example 1, Step D. Purification of theresulting oil was carried out by filtration through a plug of silica gel(50% EtOAc/PE as eluant) to give3,4-difluoro-2-(2-fluoro-4-propylanilino)-N-(2-hydroxyethoxy)benzamideas a white solid (77%); m.p. (EtOAc/hexane) 144–146° C. ¹H NMR [400 MHz,(CD₃)₂SO] δ 11.85 (br s, 1 H), 8.76 (br s, 1 H), 7.43–7.33 (m, 1H),7.14–7.06 (m, 1 H), 7.04 (dd, J=12.5, 1.5 Hz, 1 H), 6.88 (dd, J=8.3, 1.7Hz, 1H), 6.83 (ddd, J=8.6, 8.6, 4.2 Hz, 1 H), 4.70 (br s, 1 H), 3.86 (t,J=4.9 Hz, 2 H), 3.57 (t, J=4.9 Hz, 2 H), 2.49 (t, J=7.7 Hz, 2 H), 1.56(sextet, J=7.4 Hz, 2 H), 0.87 (t, J=7.3 Hz, 3 H). Anal. calcd. forC₁₈H₁₉F₃N₂O₃: C, 58.7; H, 5.2; N, 7.6. Found C, 58.8; H, 5.2; N, 7.7.

EXAMPLE 30

2-(4-Butyl-2-fluoroanilino)-3,4-difluoro-N-(2-hydroxyethoxy)benzamide

Step A: Preparation of 4-butyl-2-fluoroaniline

ZnCl₂ (5.17 g, 38.0 mmol) was weighed into a flask, which was then flamedried and flushed with N₂. Anhydrous THF (20 ml) was then added at 0°C., followed by 2.5 M ^(n)BuLi (15.2 ml, 38.0 mmol). The reactionmixture was stirred at 0° C. for 15 min, after which2-fluoro-4-iodoaniline (3.00 g, 12.7 mmol) in anhydrous THF (10 ml) andPd(PPh₃)₄ (0.74 g, 0.64 mmol) were added sequentially. The mixture wasallowed to warm to RT and stirred for a further 6 h. The mixture waspoured into ice/Et₂O, the organic layer separated and the aqueous layerfurther extracted with Et₂O. The combined organic fractions were washedwith sat. NaHCO₃, dried (Na₂SO₄) and concentrated under reducedpressure. The resulting solid was removed from the mixture by filtrationand the filtrate purified by flash chromatography on silica (12.5%EtOAc/Hexane as eluant) to give the desired product (30%, 3.7 mmol). ¹HNMR [400 MHz, CDCl₃] δ 6.80 (dd, J=12.1, 1.8 Hz, 1 H), 6.76–6.65 (m, 2H), 3.65 (br s, 2 H), 2.49 (t, J=7.7 Hz, 2 H), 1.57–1.49 (m, 2 H), 1.32(sextet, J=7.3 Hz, 2 H), 0.91 (t, J=7.3 Hz, 3 H). LCMS (ACPI⁺) 168(100%).

Step B: Preparation of 2-(4-butyl-2-fluoroanilino)-3,4-difluorobenzoicacid

2,3,4-Trifluorobenzoic acid and 4-butyl-2-fluoroaniline were reacted inthe presence of LiHMDS solution in THF by the general procedure ofExample 1, Step B, affording crude2-(4-butyl-2-fluoroanilino)-3,4-difluorobenzoic acid after workup. Thecrude material was further purified by flash chromatography on silica(10% EtOAc/Hexane as eluant) to give the desired compound (40%). ¹H NMR[400 MHz, CH₃₀D] δ 7.86 (ddd, J=8.4, 5.8, 2.1 Hz, 1 H), 6.96–6.86 (m, 3H), 6.78 (ddd, J=9.4, 9.4, 7.1 Hz, 1 H), 2.58 (t, J=7.7 Hz, 2 H),1.63–1.55 (m, 2 H), 1.36 (sextet, J=7.4, 2H), 0.94 (t, J=7.5, 3 H). LCMS(ACPI⁺) 329 (100%).

Step C: Preparation of2-(4-butyl-2-fluoroanilino)-3,4-difluoro-N-(2-hydroxyethoxy)benzamide

The title compound was prepared from reaction of2-(4-butyl-2-fluoroanilino)-3,4-difluorobenzoic acid with CDI and2-(aminooxy)ethanol by the general procedure of Example 1, Step E, thenpurified by flash column chromatography on silica (50% EtOAc/Hexane aseluant) to give2-(4-butyl-2-fluoroanilino)-3,4-difluoro-N-(2-hydroxyethoxy)benzamide asa white solid (68%); m.p. (EtOAc/Hexane) 163–165° C.

¹H NMR [400 MHz, (CD₃)₂SO] δ 11.85 (br s, 1 H), 8.74 (br s, 1 H),7.44–7.38 (m, 1H), 7.14–7.06 (m, 1 H), 7.06–7.01 (m, 1 H), 6.88 (dd,J=8.3, 1.1 Hz, 1 H), 6.83 (ddd, J=8.4, 8.4, 4.2 Hz, 1 H), 4.73 (br s, 1H), 3.87 (t, J=4.8 Hz, 2 H), 3.58 (t, J=4.8 Hz, 2 H), 2.52 (t, J=7.5 Hz,2 H), 1.57–1.48 (m, 2 H), 1.29 (sextet, J=7.3 Hz, 2 H), 0.89 (t, J=7.3Hz, 3 H). Anal. Calcd for C₁₇H₁₅F₃N₂O₃: C, 59.7; H, 5.5; N, 7.3. FoundC, 59.4; H, 5.4; N, 7.4.

EXAMPLE 31

N-[(R—)2,3-Dihydroxy-propoxy]-2-(4-ethyl-2-fluoro-phenylamino)-3,4-difluoro-benzamideStep A: Preparation of 1.2:5,6-di-O-isopropylidene-D-mannitol

To a stirring suspension of D-Mannitol (1.82 g, 10.0 mmol) intetrahydrofuran (21 mL) and dimethylformamide (9 mL) was addedp-toluenesulfonic acid monohydrate (0.02 g, 0.1 mmol,) at ambienttemperature, followed by 2,2-dimethoxypropane (2.8 mL, 0.023 mol). Thereaction mixture was stirred for 18 hours at room temperature, thenadditional 2,2-dimethoxypropane (0.3 mL, 2.4 mmol) was added. Thesuspension was heated to 40° C. to 45° C., and stirred for 2 hours.Sodium bicarbonate (1.8 g, 0.016 mol) was added to neutralize the acidand the mixture was stirred for 30 minutes. The excess Na₂CO₃ wasfiltered and washed with tetrahydrofuran (5 mL). The filtrate wasconcentrated. To the remaining light yellow oil was added toluene (15mL) and the mixture was stirred at 3° C. to 5° C. until a light-yellowgelatinous solid formed. The solid was filtered and washed with hexane(2×5 mL). The product was dried in a vacuum oven for 18 hours to give1,2:5,6-di-O-isopropylidene-D-mannitol (1.24 g, 47.3%) as an off-whitesolid, mp 110–113° C.

Step B: Preparation of(S)-(+)-(2,2-dimethyl-[1,3]dioxolan-4-yl)-methanol

To a solution of the product of Example 31, Step A,1,2:5,6-di-O-isopropylidene-D-mannitol (50 g, 0.191 mol), in water (700mL), was added solid sodium bicarbonate (20 g). The resultant solutionwas stirred until all the solid dissolved, and then cooled in anice-water bath. Solid sodium periodate (81.5 g, 0.381 mol) was slowlyadded to the solution portionwise. Gas evolution observed. The whitemixture was stirred at ambient temperature for 2 hours. Solid sodiumchloride (30 g) was added, and the mixture was stirred for 15 minutes.The white solid was filtered. The filtrate was cooled in an ice-waterbath. Solid sodium borohydride was added slowly. Gas bubbles evolved.The mixture was warmed to ambient temperature, and stirred overnight.The milky mixture turned to a clear solution. The aqueous solution wasextracted with dichloromethane (3×). The organic solution was washedwith brine, and dried over magnesium sulfate. The solvent was removed invacuo to give (S)-(+)-(2,2-dimethyl-[1,3]dioxolan-4-yl)-methanol as acolorless oil, which was dried under high vacuum at ambient temperatureovernight, 34.82 g (60%); MS (APCI+)=133 (M⁺+1).

Step C: Preparation of(R)-2-(2,2-dimethyl-[1,3]dioxolan-4-ylmethoxy)-isoindole-1,3-dione

A 3-L round-bottomed flask equipped with mechanical stirrer andadditional funnel was charged with N-hydroxyphthalimide (68.0 g, 0.416mol) and tetrahydrofuran (1.2 L) under nitrogen atmosphere. To thissolution was added triphenylphosphine (109.2 g, 0.416 mol) and theproduct of Example 31, Step B,(S)-(2,2-dimethyl-[1,3]dioxolan-4-yl)-methanol (55.0 g, 0.416 mol). Themixture was cooled to 3° C. to 5° C. and diethyl azodicarboxylate (85.2mL, 0.541 mol) was added dropwise, while keeping the inner temperaturebelow 15° C. The reaction mixture was warmed to ambient temperature, andstirred for 18 hours. The tetrahydrofuran was evaporated under reducedpressure. To the remaining orange solid was added dichloromethane (0.5L) and the mixture was stirred for 1 hour. The white solid (Ph₃PO) wasfiltered and washed with dichloromethane (0.1 L). The solvent wasremoved and ethanol (0.5 L) was added to the resulting solid. Themixture was stirred for 2 hours at 3° C. to 5° C. The white solid wasfiltered, washed with a small amount of cold EtOH, and dried in vacuumoven at 40° C. to give(R)-2-(2,2-dimethyl-[1,3]dioxolan-4-ylmethoxy)-isoindole-1,3-dione(112.5 g, 97%) as a white solid: ¹H NMR (CDCl₃): δ 1.33 (s, 3 H), 1.99(s, 3 H), 3.96 (m, 1 H), 4.15 (m, 2 H), 4.30 (m, 1 H), 4.48 (m, 1 H),7.59 (m, 2 H), 7.84 (m, 2 H); MS (APCI+)=278 (M⁺+1).

Step D: Preparation of(R)-(2,2-dimethyl-[1.3]dioxolan-4-ylmethyl)-hydroxylamine

To a stirring solution of the product of Example 31, Step C,(R)-2-(2,2-dimethyl-[1,3]dioxolan-4-ylmethoxy)-isoindole-1,3-dione (74.9g, 0.27 mol) in dichloromethane (480 mL) at 3° C. to 5° C. was addedmethylhydrazine (15.8 mL, 0.29 mol) dropwise. The color of thesuspension turned from yellow to white. The cooling bath was removed andthe mixture was stirred for 2 hours at ambient temperature. Theresulting suspension was concentrated on a rotary evaporator. To thewhite solid was added ether (0.5 L) and the resulting mixture wasstirred for 1.5 hours at ambient temperature. The white precipitate wasfiltered and washed with ether (0.2 L). The filtrate was concentrated onrotary evaporator to give(R)-(2,2-dimethyl-[1,3]dioxolan-4-ylmethyl)-hydroxylamine (39.0 g,98.3%): ¹H NMR (CDCl₃): δ 1.35 (s, 3 H), 1.42 (s, 3H), 3.73 (m, 3H),4.05 (m, 1H), 4.33 (m, 1H), 5.39 (m, 2 ) H; MS (APCI+)=148.1 (M⁺+1).

Step E: Preparation ofN-((R)-2,2-Dimethyl-[1,3]dioxolan-4-ylmethoxy)-2-(4-ethyl-2-fluoro-phenylamino)-3,4-difluoro-benzamide

To a stirring solution of the product of Example 1, Step D,2-[(4-ethyl-2-fluorophenyl)amino]-3,4-difluorobenzoic acid (0.480 g,1.626 mmol) in dichloromethane (25 mL) is added to the product ofExample 31, Step D,(R)—O-(2,2-dimethyl-[1,3]dioxan-4-ylmethyl)-hydroxylamine (0.38 g, 2.57mmol), triethylamine (0.54 mL, 3.85 mmol), andbenzotriazole-1-yl-oxy-tris-pyrrolidino-phosphonium hexafluorophosphate(1.34 g, 2.57 mmol) and allowed to stir at ambient temperature for 90minutes. The reaction mixture was concentrated in vacuo and theaffording residue was partitioned between ethyl acetate and water. Theorganic layers were washed twice with saturated sodium carbonatesolution and twice with brine. The organic layer was collected, driedover sodium sulfate, filtered and concentrated in vacuo.N-((R)-2,2-Dimethyl-[1,3]dioxolan-4-ylmethoxy)-2-(4-ethyl-2-fluoro-phenylamino)-3,4-difluoro-benzamidewas isolated via silica column chromatography in 4:1 hexanes/ethylacetate, then 3:1 hexanes/ethyl acetate affording a white foam (0.515 g,56.7%).

Step F: Preparation ofN-[(R−)2,3-dihydroxy-propoxy]-2-(4-ethyl-2-fluoro-phenylamino)-3,4-difluoro-benzamide

To a stirring solution of the product of Example 31, Step E,N-((R)-2,2-dimethyl-[1,3]dioxolan-4-ylmethoxy)-2-(4-ethyl-2-fluoro-phenylamino)-3,4-difluoro-benzamide(0.515 g, 1.213 mmol) in methanol (10 mL) and water (1 mL) was addedp-toluenesulfonic acid (0.115 g, 0.607 mmol). After stirring for 17hours the reaction mixture was partitioned between ethyl acetate andwater. The organic layer was washed twice saturated sodium carbonatesolution and twice with brine. The organic layer was collected, driedover sodium sulfate, filtered and concentrated in vacuo to affordN-[(R)-2,3-dihydroxy-propoxy]-2-(4-ethyl-2-fluoro-phenylamino)-3,4-difluoro-benzamide(0.440 g, 94.4%) as a clear oil/foam. 1NMR (400 MHz; CD₃OD) δ 7.35 (1H,m), 6.84–6.95 (3H, m), 6.76–6.79 (1H, m), 3.91–3.94 (1H, m), 3.81–3.85(2H, m), 3.53–3.55 (2H, m), 2.57 (2H, q, J=15.1, 7.6 Hz), 1.19 (3H, t,J=7.6 Hz); ¹⁹F-NMR (376 MHz; CD₃OD) δ −132.3, −134.8, −147.3;MS(APCI+)=385; Anal. calcd/found for C₁₈H₁₉F₃N₂O₄: C, 56.25/56.22; H,4.98/4.93; N, 7.29/7.17; [α]²⁵ _(D) −5.6° (c 10.8, EtOH).

EXAMPLE 32

N-[(S+)2,3-Dihydroxy-propoxy]-2-(4-ethyl-2-fluoro-phenylamino)-3,4-difluoro-benzamideStep A: Preparation of L-gulonic γ-lactone

To a solution of L-ascorbic acid in water is added Pd/C (10%). Themixture is subjected to hydrogenation in a Parr hydrogenator at 48 psi,18° C. for about 2 to 3 days. The reaction mixture is filtered and thefiltrate is concentrated in vacuo to afford L-gulonic γ-lactone, afterdrying at 50° C. in a vacuum oven for about 1 to 3 hours.

Step B: Preparation of 5,6-isopropylidene-L-gulonic Acid γ-lactone

The product of Example 32, Step A, L-gulonic γ-lactone is dissolved in amixture of tetrahydrofuran and dimethylformamide. p-Toluenesulfonic acidmonohydrate is added and the reaction mixture is cooled to 0° C. to 5°C. in an ice-water bath. 2,2-Dimethoxypropane is added dropwise, and thereaction mixture is stirred at ambient temperature for about 1 to 3hours. The mixture is neutralized with solid sodium carbonate andstirred for about 1 hour. The solid is filtered and washed withtetrahydrofuran. The THF is removed under vacuo, and DMF by distillationunder high vacuum. The resulting orange solid is triturated withtoluene, filtered, washed with toluene, and dried in a vacuum oven at40° C. for about 3 days, to yield 5,6-isopropylidene-L-gulonic Acidγ-lactone.

Step C: Preparation of(R)-(+)-(2,2-dimethyl-[1,3]dioxolan-4-yl)-methanol

To a stirring suspension of the product of Example 32, Step B,5,6-O-isopropylidene-L-gulono-1,4-lactone, in water is added solidsodium periodate in small portions at 3° C. to 5° C. The pH of themixture is adjusted to 5.5 with 1N aqueous sodium hydroxide. Thesuspension is stirred for 2 hours at ambient temperature, then saturatedwith sodium chloride and filtered. To the filtrate, at 3° C. to 5° C.,is added sodium borohydride in small portions. The reaction mixture isstirred for 18 hours at ambient temperature. Acetone is added to destroythe excess of sodium borohydride, and the stirring is continued for 30minutes. The acetone is removed under reduced pressure and the aqueousresidue is extracted with dichloromethane and EtOAc. The combinedorganic layers are dried over magnesium sulfate, filtered, andevaporated to give (R)-(+)-(2,2-dimethyl-[1,3]dioxolan-4-yl)-methanol.

Step D: Preparation of(S)—O-(2,2-dimethyl-[1,3]dioxolan-4-ylmethyl)-hydroxylamine

By the general procedure of Example 31, Step C and Step D, the productof Example 32, Step C,(R)-(+)-(2,2-dimethyl-[1,3]dioxolan-4-yl)-methanol is used to provide(S)-O-(2,2-dimethyl-[1,3]dioxolan-4-ylmethyl)-hydroxylamine.

Step E: Preparation ofN-[(S+)2,3-Dihydroxy-propoxy]-2-(4-ethyl-2-fluoro-phenylamino)-3,4-difluoro-benzamide

By the general procedure of Example 31, Step E and Step F, the productof Example 32, Step D,(S)-O-(2,2-dimethyl-[1,3]dioxolan-4-ylmethyl)-hydroxylamine is used toprovideN-[(S+)2,3-Dihydroxy-propoxy]-2-(4-ethyl-2-fluoro-phenylamino)-3,4-difluoro-benzamide.

EXAMPLE 33

2-(4-Ethyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-1-hydroxymethyl-ethoxy)-benzamideStep A: Preparation of2-(2,2-dimethyl-[1,3]dioxan-5-yloxy)-isoindole-1,3-dione

2,2-Dimethyl-[1,3]dioxan-5-ol was prepared as described previously(Forbes, D. C. et al.; Synthesis, 1998; 6:879–882). ¹H NMR (400 MHz;DMSO-d₆) δ 4.91 (d, 1H, J=5.1), 3.70–3.75 (m, 2 H), 3.41–3.46 (m, 3 H),1.30 (s, 3 H), 1.24 (s, 3 H); MS (APCI+)=132.9. To a stirring solutionof 2,2-dimethyl-[1,3]dioxan-5-ol (1.50 g, 11.35 mmol),N-hydroxyphthalimide (1.85 g, 11.35 mmol), and triphenylphosphine (2.98g, 11.35 mmol) in anhydrous tetrahydrofuran (30 mL) at 0° C. was addeddiethyl azodicarboxylate (2.3 mL, 14.75 mmol). The resultant solutionwas allowed to warm to room temperature. After stirring for 3 hours, themixture was concentrated in vacuo and charged with chloroform affordingwhite solids. The solids were filtered off and filtrate was collectedand concentrated. The residue was purified via silica columnchromatography (4:1 hexanes/ethyl acetate) affording2-(2,2-dimethyl-[1,3]dioxan-5-yloxy)-isoindole-1,3-dione as clearcrystals (1.74 g, 55% over 2 steps): ¹H NMR (400 MHz; DMSO-d₆) δ 7.83(s, 4 H), 4.11–4.12 (m, 1 H), 4.04–4.09 (m, 2 H), 3.92–3.96 (m, 2 H),1.32 (s, 3 H), 1.25 (s, 3 H); MS (APCI+)=278.0.

Step B: Preparation of O-(2,2-dimethyl-[1,3]dioxan-5-yl)-hydroxylamine

To a stirring solution of the product of Example 33, Step A,2-(2,2-dimethyl-[1,3]dioxan-5-yloxy)-isoindole-1,3-dione (1.72 g, 6.20mmol), in dichloromethane (15 mL) at 0° C. under nitrogen was addedmethylhydrazine (0.36 mL, 6.82 mmol) and allowed to warm to roomtemperature. After stirring for 2 hours the reaction mixture wasconcentrated in vacuo and charged with diethylether. The solids werefiltered off and the filtrate was collected and concentrated to affordO-(2,2-dimethyl-[1,3]dioxan-5-yl)-hydroxylamine as a yellow oil (0.97 g,100%). ¹H NMR (400 MHz;DMSO-d₆) δ 5.98 (bs, 2 H), 3.84–3.87 (m, 2 H),3.66–3.68 (m, 2 H), 3.30–3.35 (m, 1 H), 1.29 (s, 3 H), 1.22 (s, 3 H); MS(APCI+)=147.9.

Step C: Preparation ofN-(2,2-dimethyl-[1,3]dioxan-5-yloxy)-2-(4-ethyl-2-fluoro-phenylamino)-3,4-difluoro-benzamide

To a stirring solution of the product of Example 1, Step D,2-[(4-ethyl-2-fluorophenyl)amino]-3,4-difluorobenzoic acid (0.480 g,1.626 mmol) in dichloromethane (15 mL) is added the product of Example33, Step B, O-(2,2-dimethyl-[1,3]dioxan-5-yl)-hydroxylamine (0.287 g,1.951 mmol), triethylamine (0.41 mL, 2.927 mmol), andbenzotriazole-1-yl-oxy-tris-pyrrolidino-phosphonium hexafluorophosphate(1.02 g, 1.951 mmol) and allowed to stir at ambient temperature for 75minutes. The reaction mixture was concentrated in vacuo and theaffording residue was partitioned between ethyl acetate and water. Theorganic layers were washed twice with saturated sodium carbonatesolution and twice with brine. The organic layer was collected, driedover sodium sulfate, filtered and concentrated in vacuo.N-(2,2-Dimethyl-[1,3]dioxan-5-yloxy)-2-(4-ethyl-2-fluoro-phenylamino)-3,4-difluoro-benzamidewas isolated via silica column chromatography in 4:1 hexanes/ethylacetate affording a white foam (0.423 g, 61.4%).

Step D:2-(4-Ethyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-1-hydroxymethyl-ethoxy)-benzamide

To a stirring solution of the product of Example 33, Step C,N-(2,2-dimethyl-[1,3]dioxan-5-yloxy)-2-(4-ethyl-2-fluoro-phenylamino)-3,4-difluoro-benzamide(0.416 g, 0.980 mmol) in ethanol (5 mL) was added 1 molar aqueoushydrochloric acid solution (1 mL). After stirring for 1 hour at ambienttemperature the reaction mixture was partitioned between ethyl acetateand water. The organic layer was washed twice with water and twice withbrine. The organic layer was collected, dried over sodium sulfate,filtered and concentrated in vacuo. The affording foam was crystallizedin ethyl acetate and heptane to afford2-(4-ethyl-2-fluoro-phenylamino)-3,4-difluoro-N-(2-hydroxy-1-hydroxymethyl-ethoxy)-benzamide(0.318 g, 84.6%) as a white crystalline solid: m.p. 91–93° C.; ¹NMR (400MHz; CD₃OD) δ 7.38 (1H, t, J=6.8 Hz), 6.85–6.96 (3H, m), 6.73–6.78 (1H,m), 3.86–3.82 (1 H), 3.64 (4H, d, J=4.9 Hz), 2.58 (2H, q, J=15.1, 7.6Hz), 1.19 (3H, t, J=7.6 Hz); ¹⁹F-NMR (376 MHz; CD₃OD) 8–132.4, −134.6,−147.2; MS(APCI+)=385; Anal.calcd/found for C₁₈H₁₉F₃N₂O₄: C,56.25/56.38; H, 4.98/4.81; N, 7.29/7.25.

EXAMPLE 34

Cellular Assay for Measuring MEK Inhibition

The evaluation of the compounds as MEK inhibitors is performed in anassay that measures their ability to inhibit phosphorylation of MAPkinase (ERK) in murine colon 26 (C26) carcinoma cells. Since ERK1 andERK2 represent the only known substrates for MEK, measurement ofinhibition of ERK phosphorylation in cells provides direct readout ofcellular MEK inhibition by the compounds of the invention. Briefly, theassay involves treating exponentially growing C26 cells with varyingconcentrations of the test compound (or vehicle control) for 1 hour at37° C. Cells are then rinsed free of compound/vehicle and lysed in asolution containing 70 mM NaCl, 50 mM glycerol phosphate, 10 mM HEPES,pH 7.4, 1% Triton X-100, 1 mM Na₃VO₄, 100 μM PMSF, 10 μM leupeptin, and10 μM pepstatin. Supernatants are then subjected to gel electrophoresisand Western blotting using a primary antibody recognizing duallyphosphorylated ERK1 and ERK2. To evaluate total MAPK levels, blots weresubsequently ‘stripped’ and re-probed with a 1:1 mixture of polyclonalantibodies recognizing unphosphorylated ERK1 and ERK2.

The inhibition data generated by the above protocol is disclosed inTable 1. If several concentrations of inhibitor were tested, IC₅₀ values(the concentration which gives 50% inhibition) were determinedgraphically from the dose response curve for % inhibition. Otherwise,percent inhibitions at measured concentrations are reported.

Table I. Cellular Inhibition of ERK Phosphorylation by Compounds of theInvention

Compound of Example No. IC₅₀ (μM) 1 0.0028 2 0.0086 3 0.00015 4 0.0026 50.0079 0.018000 6 0.0078 7 0.00015 8 0.004 9 0.467 10 0.13 11 0.712 >3.000000 13 >1.000000 14 >1.000000 15 >1.000000 16 >1.00000017 >1.000000 18 0.0019 0.150000 19 0.028 0.68 20 0.0021 0.125 21 0.8 230.2 24 0.59 25 0.022 26 0.00085 27 0.0022 28 0.72 29 0.0041 30 0.19 320.002

EXAMPLE 35

Carrageenan-induced Footpad Edema (CFE) Rat Model

Male outbred Wistar rats (135–150 g, Charles River Labs) are dosedorally with 10 mL/kg vehicle or test compound 1 hour prior toadministration of a sonicated suspension of carrageenan (1 mg/0.1 mLsaline). Carrageenan is injected into the subplantar region of the righthind paw. Paw volume is determined by mercury plethysmographyimmediately after injection and again five hours after carrageenaninjection. Percent inhibition of edema is determined, and the ID40calculated by linear regression. Differences in swelling compared tocontrol animals are assessed by a 1-way ANOVA, followed by Dunnett'stest.

EXAMPLE 36

Collagen-Induced Arthritis in Mice

Type II collagen-induced arthritis (CIA) in mice is an experimentalmodel of arthritis that has a number of pathologic, immunologic, andgenetic features in common with rheumatoid arthritis. The disease isinduced by immunization of DBA/1 mice with 100 μg type II collagen,which is a major component of joint cartilage, delivered intradermallyin Freund's complete adjuvant. The disease susceptibility is regulatedby the class II MHC gene locus, which is analogous to the association ofrheumatoid arthritis with HLA-DR4.

A progressive and inflammatory arthritis develops in the majority ofmice immunized, characterized by paw width increases of up to 100%. Atest compound is administered to mice in a range of amounts, such as 20,60, 100, and 200 mg/kg body weight/day. The duration of the test can beseveral weeks to a few months, such as 40, 60, or 80 days. A clinicalscoring index is used to assess disease progression from erythema andedema (stage 1), joint distortion (stage 2), to joint ankylosis (stage3). The disease is variable in that it can affect one or all paws in ananimal, resulting in a total possible score of 12 for each mouse.Histopathology of an arthritic joint reveals synovitis, pannusformation, and cartilage and bone erosions. All mouse strains that aresusceptible to CIA are high antibody responders to type II collagen, andthere is a marked cellular response to CII.

EXAMPLE 37

SCW-induced Monoarticular Arthritis

Arthritis is induced as described by Schwab et al., Infection andImmunity, 1991; 59:4436–4442 with minor modifications. Rats receive 6 μgsonicated SCW [in 10 μL Dulbecco's PBS (DPBS)] by an intraarticularinjection into the right tibiotalar joint on Day 0. On Day 21, the DTHis initiated with 100 μg of SCW (250 μL) administered IV. For oralcompound studies, compounds are suspended in vehicle (0.5%hydroxypropyl-methylcellulose/0.2% Tween 80), sonicated, andadministered twice daily (10 mL/kg volume) beginning 1 hour prior toreactivation with SCW. Compounds are administered in amounts between 10and 500 mg/kg body weight/day, such as 20, 30, 60, 100, 200, and 300mg/kg/day. Edema measurements are obtained by determining the baselinevolumes of the sensitized hindpaw before reactivation on Day 21, andcomparing them with volumes at subsequent time points such as Day 22,23, 24, and 25. Paw volume is determined by mercury plethysmography.

EXAMPLE 38

Mouse Ear-heart Transplant Model

Fey T. A. et al. describe methods for transplanting split-heart neonatalcardiac grafts into the ear pinna of mice and rats (J. Pharm. and Toxic.Meth., 1998; 39:9–17). Compounds are dissolved in solutions containingcombinations of absolute ethanol, 0.2% hydroxypropyl methylcellulose inwater, propylene glycol, cremophor, and dextrose, or other solvent orsuspending vehicle. Mice are dosed orally or intraperitoneally once,twice or three times daily from the day of transplant (Day 0) throughDay 13 or until grafts have been rejected. Rats are dosed once, twice,or three times daily from Day 0 through Day 13. Each animal isanesthetized and an incision is made at the base of the recipient ear,cutting only the dorsal epidermis and dermis. The incision is spreadopen and down to the cartilage parallel to the head, and sufficientlywide to accommodate the appropriate tunneling for a rat or insertiontool for a mouse. A neonatal mouse or rat pup less than 60 hours old isanesthetized and cervically dislocated. The heart is removed from thechest, rinsed with saline, bisected longitudinally with a scalpel, andrinsed with sterile saline. The donor heart fragment is placed into thepreformed tunnel with the insertion tool and air or residual fluid isgently expressed from the tunnel with light pressure. No suturing,adhesive bonding, bandaging, or treatment with antibiotics is required.

Implants are examined at 10- to 20-fold magnification with astereoscopic dissecting microscope without anesthesia. Recipients whosegrafts are not visibly beating may be anesthetized and evaluated for thepresence of electrical activity using Grass E-2 platinum subdermal pinmicroelectodes placed either in the pinna or directly into the graft anda tachograph. Implants can be examined 1 to 4 times a day for 10, 20, 30or more days. The ability of a test compound to ameliorate symptoms oftransplant rejection can be compared with a control compound such ascyclosporine, tacrolimus, or orally-administered lefluonomide.

EXAMPLE 39

The analgesic activity of the compounds of the present invention isassessed by a test with rats. Rats weighing from 175 to 200 g areinjected with carrageenan (2% in 0.9% sodium chloride aqueous solution,100 μL injection volume) into the footpad of one hind limb. The rats areplaced on a glass plate with illumination from a halogen lamp placeddirectly under the injected paw. The time (in seconds) from beginningillumination until the hindlimb was withdrawn from the glass wasmeasured and scored as Paw Withdrawal Latency (PWL). Drug substanceswere given by oral gavage injection 2½ hours after carrageenan injectionto the footpad. PWL was measured prior to carrageenan injection, justprior to drug injection, and 1, 2 (and sometimes 3) hours after druginjection.

Carrageenan (a polysaccharide extracted from seaweed) causes a sterileinflammation when injected under the skin. Injection into the ratfootpad causes little or no spontaneous pain-related behavior butinduces hyperalgesia (pain-related behavioral responses of greaterintensity than expected) to peripheral thermal or mechanical stimuli.This hyperalgesia is maximal 2 to 3 hours after injection. Treatment ofrats with various analgesic drugs reduces hyperalgesia measured in thisway and is a conventional test for detection of analgesic activity inrats. (Hargreaves K, Dubner R, Brown F, Flores C, Joris J. A new andsensitive method for measuring thermal nociception in cutaneoushyperalgesia. Pain, 1988; 32:77–88 and Kayser V, Guilbaud G. Local andremote modifications of nociceptive sensitivity duringcarrageenan-induced inflammation in the rat. Pain, 1987; 28:99–108).Untreated rats have a PWL of approximately 10 seconds. Carrageenaninjection reduces PWL to approximately 3 seconds for at least 4 hours,indicating thermal hyperalgesia. Inhibition of the carrageenan thermalhyperalgesia response is determined by the difference between reducedPWL prior to drug and subsequent to drug treatment, and was expressed aspercent inhibition of the response. Administration of MEK inhibitorsdose-dependently reduced thermal hyperalgesia.

1. A method of treating arthritis in a patient in need thereofcomprising administering a therapeutically effective amount of acompound of formula I

wherein W is

R₂ is hydrogen, methyl, fluorine, or chlorine; R₃ is hydrogen orfluorine; R₄ is C₁₋₆ alkyl, C₂₋₄ alkenyl, C₂₋₆ alkynyl, C₃₋₆ cycloalkyl,—(CH₂)—C₃₋₆ cycloalkyl, —O—(C₁₋₄ alkyl), —S—(C₁₋₂ alkyl), —SO₂CH₃,—SO₂NR₆R₇, —C≡C—(CH₂)_(n)NH₂, —C═C(CH₂)_(n)OH, —C═C—(CH₂)_(n)NH₂,—(CH₂)_(m)NH₂, —(CH₂)_(m)NHCH₃, —(CH₂)_(m)N(CH₃)₂, —(CH₂)_(m)OR₈,—(CH₂)_(q)CF₃, —C≡CCF₃, —CH═CHCF₃, —CH₂CHCF₂, or —CH═CF₂, wherein theC₁₋₆ alkyl and C₂₋₆ alkynyl are optionally substituted with between 1and 3 substituents selected from hydroxy and alkyl; m is 1 to 4; n is 1to 2; q is 0 to 2; R₅ is hydrogen or chlorine; R₆ and R₇ are eachindependently hydrogen, methyl, or ethyl; R₈ is independently methyl orethyl; or a pharmaceutically acceptable salt thereof.
 2. The method ofclaim 1 wherein the arthritis is rheumatoid arthritis.
 3. The method ofclaim 1 wherein the arthritis is osteoarthritis.
 4. A method of treatingchronic pain in a patient in need thereof comprising administering atherapeutically effective amount of a compound of formula I

wherein W is

R₂ is hydrogen, methyl, fluorine, or chlorine; R₃ is hydrogen orfluorine; R₄ is C₁₋₆ alkyl, C₂₋₄ alkenyl, C₂₋₆ alkynyl, C₃₋₆ cycloalkyl,—(CH₂)—C₃₋₆ cycloalkyl, —O—(C₁₋₄ alkyl), —S—(C₁₋₂ alkyl), —SO₂CH₃,—SO₂NR₆R₇, —C≡C—(CH₂)_(n)NH₂, —C═C(CH₂)_(n)OH, —C═C—(CH₂)_(n)NH₂,—(CH₂)_(m)NH₂, —(CH₂)_(m)NHCH₃, —(CH₂)_(m)N(CH₃)₂, —(CH₂)_(m)OR₈,—(CH₂)_(q)CF₃, —C≡CCF₃, —CH═CHCF₃, —CH₂CHCF₂, or —CH═CF₂, wherein theC₁₋₆ alkyl and C₂₋₆ alkynyl are optionally substituted with between 1and 3 substituents selected from hydroxy and alkyl; m is 1 to 4; n is 1to 2; q is 0 to 2; R₅ is hydrogen or chlorine; R₆ and R₇ are eachindependently hydrogen, methyl, or ethyl; R₈ is independently methyl orethyl; or a pharmaceutically acceptable salt thereof.
 5. The method ofclaim 4, wherein the chronic pain is selected from the group consistingof neuropathic pain, idiopathic pain, and pain associated with chronicalcoholism, vitamin deficiency, uremia, and hypothyroidism.
 6. Themethod of claim 4, wherein the chronic pain is associated withinflammation.
 7. The method of claim 4, wherein the chronic pain isassociated with arthritis.
 8. The method of claim 4, wherein the chronicpain is associated with post-operative pain.
 9. The method of claim 5,wherein the chronic pain is the neuropathic pain.
 10. The method ofclaim 9, wherein the neuropathic pain is associated with a conditionselected from the group consisting of inflammation, postoperative pain,phantom limb pain, burn pain, gout, trigeminal neuralgia, acute herpeticand postherpetic pain, causalgia, diabetic neuropathy, plexus avulsion,neuroma, vasculitis, viral infection, crush injury, constriction injury,tissue injury, limb amputation, arthritis pain, and nerve injury betweenthe peripheral nervous system and the central nervous system.